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Rocky Mountain Spotted Fever

RMSF

Rocky Mountain spotted fever (RMSP) is a frequent illness caused by the species Rickettsia rickettsii of the genus Rickettsia, a group of Gram-negative and highly pleomorpic bacteria responsible for diseases such as typhus and rickettsialpox.


Presentation

The initial RMSF presentation is characterized by the classical triad of fever, headache and rash, which begins to appear after 3 to 4 days from pathogen exposure. A history of tick bite is present only in two thirds of the cases, because the bite itself is painless and subjects do not even remember being bitten. The incubation period may span from 2 to 8 days, and a clear picture of the illness becomes evident only in the second week from exposure, with the appearance of other classical signs such as muscle and joint pain, lack of appetite and forgetfulness.

Most frequent are also CNS symptoms like encephalitis (which later progresses to stupor, delirium and coma) and gastrointestinal signs, like nausea, vomiting and abdominal pain. It is important to note that this clinical picture is nonspecific and the combination of symptoms varies greatly from patient to patient. Thus, Rocky Mountain spotted fever is difficult to diagnose and frequently confused with other nonspecific febrile illnesses. For this reason RMSF has also been defined as the “great imitator” of other diseases [15].

Rash is among the most important pathognomic features of Rocky Mountain spotted fever and usually appears only by the second or third day from exposure. It has a typical centripetal or “inward” diffusion pattern. It begins at the extremities and moves towards the trunk and the central parts of the body. Rash initially appears with blanching maculopapular lesions, which slowly turn in petechial lesions after 6 days on the palms of the hands and the soles of the feet. The prompt recognition of maculopapular eruption is vital for diagnosis, because the appearance of petechial spots is a clear sign of the RMSF advanced stage.

Splenomegaly
  • Mucosal ulcers, postinflammatory hyperpigmentation, jaundice, cough, pneumonia, acute renal failure, lymphadenopathy, hepatomegaly, splenomegaly, conjunctivitis, peripheral, periorbal and optic disk oedema, arterial occlusion, retinal vein engorgement[canada.ca]
Fever
  • Abstract Initial symptoms of Rocky Mountain spotted fever (RMSF), a tick-borne illness caused by Rickettsia rickettsii, are nonspecific and include headache, gastrointestinal disturbances, malaise, and myalgias, followed by fever and rash.[ncbi.nlm.nih.gov]
  • […] salt solution serum virus sheep smears spotted-fever strains suspension symptoms Tarle temperature test area tick virus tion tissue virus titration typhus typical spotted fever U.[books.google.com.au]
  • From 2002 through 2004, a focus of Rocky Mountain spotted fever was investigated in rural eastern Arizona. METHODS: We obtained blood and tissue specimens from patients with suspected Rocky Mountain spotted fever and ticks from patients' homesites.[ncbi.nlm.nih.gov]
  • Rocky Mountain spotted fever should be added to the list of conditions associated with the adult respiratory distress syndrome. This case also illustrates the difficulties in distinguishing Rocky Mountain spotted fever from atypical measles.[ncbi.nlm.nih.gov]
  • Abstract Rocky Mountain spotted fever and Mediterranean spotted fever are rickettsial infections primarily of endothelial cells that normally have a potent anticoagulant function.[ncbi.nlm.nih.gov]
Chills
  • Abstract A 32-year-old black man from rural southeastern Texas had headache, fever, chills, bronchopneumonia, and an atypical rash, complicated by hypotension, lethargy, confusion, liver dysfunction, thrombocytopenia, and acute renal failure.[ncbi.nlm.nih.gov]
  • Definition of Rocky Mountain spotted fever : an acute disease that is characterized by chills, fever, prostration, pains in muscles and joints, and a red to purple eruption and that is caused by a rickettsial bacteria ( Rickettsia rickettsii ) usually[merriam-webster.com]
  • In addition to the rash, the infection can cause fever, chills, muscle aches, vomiting, and nausea. Typically, RMSF is treated with antibiotics and patients recover without any complications.[kidshealth.org]
  • The abrupt onset of the disease includes severe headache, fever, chills, arthralgia, and myalgia. After 2–3 days of these constitutional symptoms, erythematous macules erupt on the wrists, hands, forearms, legs, and ankles, as seen in these figures.[webmd.com]
  • They may include: Chills and fever Confusion Headache Muscle pain Rash -- usually starts a few days after the fever; first appears on wrists and ankles as spots that are 1 to 5 mm in diameter, then spreads to most of the body.[nlm.nih.gov]
Malaise
  • Abstract Initial symptoms of Rocky Mountain spotted fever (RMSF), a tick-borne illness caused by Rickettsia rickettsii, are nonspecific and include headache, gastrointestinal disturbances, malaise, and myalgias, followed by fever and rash.[ncbi.nlm.nih.gov]
  • The patient had no dental problems other than the need for routine prophylaxis but mentioned a recent problem with swelling of her extremities with an accompanying rash and general malaise and soreness in her neck region.[ncbi.nlm.nih.gov]
  • RMSF should be suspected in any pregnant woman presenting with fever, malaise and rash in regions where R. rickettsii is endemic.[ncbi.nlm.nih.gov]
  • Symptoms can include fever, headache, photophobia, malaise, myalgias, and a petechial rash that begins on the wrists and ankles and spreads to the trunk.[ncbi.nlm.nih.gov]
Camping
  • Kenley’s family says she had just gone camping before the sickness started. Within five days they say the infection took over her small body.[fox59.com]
  • A chemical known as permethrin is also highly effective in preventing ticks as well, and it can be sprayed on boots, clothing and even camping gear.[foxnews.com]
  • Critical Essential Core Tested Community Questions (1) (M2.ID.79) A 26-year-old male with no significant past medical history goes camping with several friends in Virginia.[medbullets.com]
  • --The little girl who died of Rocky Mountain Spotted Fever got it from a tick on a camping trip. But, it's not that common in Indiana, said the doctor who treated Kenley Ratliff at Riley Children's Health.[wibc.com]
  • Domi, 18, made a strong bid to make the Coyotes roster at training camp, but near the end of camp the team decided it was best for him to return to the OHL for a third season.[coyotes.nhl.com]
High Fever
  • There is a high fever — often 103 -105 F (39 -40 C) — with chills, muscle aches, and a severe headache. Eyes can become red, muscles may feel tender, and there may be abdominal pain, nausea, vomiting, poor appetite, and fatigue.[kidshealth.org]
  • See your doctor immediately if you have been bitten by a tick and experience sudden onset of high fever, deep muscle pain, severe headache and chills.” A rash may also develop but is often absent in the first few days.[nebraska.tv]
  • Early clinical manifestations of RMSF include high fever, severe headache, myalgias, nausea, and vomiting. Later manifestations include rash, photophobia, confusion, ataxia, seizures, cough, dyspnea, arrhythmias, jaundice, and severe abdominal pain.[visualdx.com]
  • Tick-borne spotted fevers are characterized by a sudden onset of moderate to high fever (which can last for two or three weeks), severe headache, fatigue, deep muscle pain, chills and rash.[doh.sd.gov]
  • The disease is characterized by a sudden onset of moderate to high fever (which can last for 2 or 3 weeks), severe headache, fatigue, deep muscle pain, chills and rash.[ct.gov]
Cough
  • Later manifestations include rash, photophobia, confusion, ataxia, seizures, cough, dyspnea, arrhythmias, jaundice, and severe abdominal pain. Rash occurs more frequently in children and young adults than in older individuals.[visualdx.com]
  • In addition to the early symptoms, cough, bleeding, edema, confusion, focal neurologic signs, and seizures may also be present.[aocd.org]
  • Lung (pulmonary) involvement may be suggested by various symptoms and findings, such as coughing; increasing difficulties breathing (dyspnea); inflammation of the lungs (pneumonia); an abnormal accumulation of fluid between layers of the membrane lining[rarediseases.org]
  • Mucosal ulcers, postinflammatory hyperpigmentation, jaundice, cough, pneumonia, acute renal failure, lymphadenopathy, hepatomegaly, splenomegaly, conjunctivitis, peripheral, periorbal and optic disk oedema, arterial occlusion, retinal vein engorgement[canada.ca]
Vomiting
  • Abstract Rocky Mountain spotted fever can present with predominantly abdominal symptoms including nausea, vomiting, diarrhea, and abdominal pain. Two elderly patients presented with an acute febrile illness and abdominal symptoms.[ncbi.nlm.nih.gov]
  • Abstract Recent clinical studies have shown a high incidence of nausea, vomiting, diarrhea, and abdominal pain in Rocky Mountain spotted fever (RMSF), and case reports have documented rickettsial infection and vascular injury in the small intestine, appendix[ncbi.nlm.nih.gov]
  • RESULTS: Children with RMSF presented to study institutions after a median of 6 days of symptoms, which most commonly included fever (98%), rash (97%), nausea and/or vomiting (73%), and headache (61%); no other symptom or sign was present in 50% of children[ncbi.nlm.nih.gov]
  • All patients initially had several nonspecific signs and symptoms, including fever, headache, nausea, vomiting, or myalgia, but deteriorated rapidly without receipt of a tetracycline-class antimicrobial drug.[ncbi.nlm.nih.gov]
  • Two weeks after the second dog died, the owner was examined because of severe headache, fever, nausea, vomiting, decreased appetite, lethargy, and a fine rash on the body, face, and trunk.[ncbi.nlm.nih.gov]
Nausea
  • Abstract Rocky Mountain spotted fever can present with predominantly abdominal symptoms including nausea, vomiting, diarrhea, and abdominal pain. Two elderly patients presented with an acute febrile illness and abdominal symptoms.[ncbi.nlm.nih.gov]
  • Abstract Recent clinical studies have shown a high incidence of nausea, vomiting, diarrhea, and abdominal pain in Rocky Mountain spotted fever (RMSF), and case reports have documented rickettsial infection and vascular injury in the small intestine, appendix[ncbi.nlm.nih.gov]
  • RESULTS: Children with RMSF presented to study institutions after a median of 6 days of symptoms, which most commonly included fever (98%), rash (97%), nausea and/or vomiting (73%), and headache (61%); no other symptom or sign was present in 50% of children[ncbi.nlm.nih.gov]
  • All patients initially had several nonspecific signs and symptoms, including fever, headache, nausea, vomiting, or myalgia, but deteriorated rapidly without receipt of a tetracycline-class antimicrobial drug.[ncbi.nlm.nih.gov]
  • Multiple factors increased the risk of doxycycline delay and fatal outcome, such as early symptoms of nausea and diarrhea, history of alcoholism or chronic lung disease, and abnormal laboratory results such as elevated liver aminotransferases.[ncbi.nlm.nih.gov]
Abdominal Pain
  • Abstract Rocky Mountain spotted fever can present with predominantly abdominal symptoms including nausea, vomiting, diarrhea, and abdominal pain. Two elderly patients presented with an acute febrile illness and abdominal symptoms.[ncbi.nlm.nih.gov]
  • Other signature symptoms include headache and abdominal pain. The antibiotic therapy of choice for R. rickettsii infection is doxycycline.[ncbi.nlm.nih.gov]
  • Abstract Recent clinical studies have shown a high incidence of nausea, vomiting, diarrhea, and abdominal pain in Rocky Mountain spotted fever (RMSF), and case reports have documented rickettsial infection and vascular injury in the small intestine, appendix[ncbi.nlm.nih.gov]
  • The following symptoms are commonly seen with this disease; fever, rash (occurs 2-5 days after fever, may be absent in some cases; see below), headache , nausea, vomiting, abdominal pain (may mimic appendicitis or other causes of acute abdominal pain)[health.ri.gov]
  • Typical symptoms include fever, headache, abdominal pain, vomiting, and muscle pain. A rash can also develop. RMSF can be a severe and fatal disease is not treated in the first few days of symptoms.[health.utah.gov]
Hypotension
  • Abstract A 32-year-old black man from rural southeastern Texas had headache, fever, chills, bronchopneumonia, and an atypical rash, complicated by hypotension, lethargy, confusion, liver dysfunction, thrombocytopenia, and acute renal failure.[ncbi.nlm.nih.gov]
  • The endothelial cell injury triggers a series of important physiological modifications, like increased vascular permeability, edema, hypotension and hypoalbuminemia, which cause the blood vessels to become blocked and inflamed (vasculitis).[symptoma.com]
  • Hypotension develops in severe cases. Hepatomegaly may be present, but jaundice is infrequent. Nausea and vomiting are common. Localized pneumonitis may occur.[msdmanuals.com]
  • Endothelial injury, leakage of fluid from blood vessels, and additional changes may lead to an abnormally decreased volume of blood circulating in the body (hypovolemia) and low blood pressure (hypotension).[rarediseases.org]
Hepatomegaly
  • Hepatomegaly may be present, but jaundice is infrequent. Nausea and vomiting are common. Localized pneumonitis may occur. Untreated patients may develop pneumonia, tissue necrosis, and circulatory failure, sometimes with brain and heart damage.[msdmanuals.com]
  • Mucosal ulcers, postinflammatory hyperpigmentation, jaundice, cough, pneumonia, acute renal failure, lymphadenopathy, hepatomegaly, splenomegaly, conjunctivitis, peripheral, periorbal and optic disk oedema, arterial occlusion, retinal vein engorgement[canada.ca]
Hepatosplenomegaly
  • Some individuals with RMSF may also develop abnormal enlargement of the liver and/or spleen (hepatosplenomegaly).[rarediseases.org]
Photophobia
  • Symptoms can include fever, headache, photophobia, malaise, myalgias, and a petechial rash that begins on the wrists and ankles and spreads to the trunk.[ncbi.nlm.nih.gov]
  • Later manifestations include rash, photophobia, confusion, ataxia, seizures, cough, dyspnea, arrhythmias, jaundice, and severe abdominal pain. Rash occurs more frequently in children and young adults than in older individuals.[visualdx.com]
  • Initial symptoms include sudden onset of: [ Biggs, 2016 ] Fever, chills Headache Malaise, myalgia, anorexia Nausea, vomiting, and abdominal pain Photophobia Rash ? [ Biggs, 2016 ] Begins as small, blanching pink macule on ankles, wrists/forearms.[pedemmorsels.com]
  • Other neurologic manifestations include meningitis, cranial neuropathies, deafness, paralysis, spasticity, vertigo, aphasia, and photophobia. Ophthalmologic complications can also occur.[columbia-lyme.org]
  • […] usually include a fever that may reach 103 or 104 degrees Fahrenheit; chills; extreme exhaustion (prostration); muscle pain (myalgia); and severe headaches that are often associated with pain upon moving the eyes and increased sensitivity to light (photophobia[rarediseases.org]
Red Eye
  • According to the CDC, symptoms of Rocky Mountain Spotted Fever include fever, headache, nausea, vomiting, abdominal pain, muscle pain, lack of appetite, red eyes and rash. The rash usually occurs 2-5 days after a fever begins.[wymt.com]
  • Symptoms may include: Fever Headache Rash—begins as small, flat pink spots on wrists and ankles Nausea and vomiting Abdominal pain Muscle or joint pain Lack of appetite Red eyes Light hurting the eyes Fatigue Altered mental status Severe bleeding Difficulty[cancercarewny.com]
  • If untreated, RMSF can lead to serious health problems, so it's important to call your doctor promptly if you notice any symptoms of RMSF, such as: high fever headache chills muscle aches red eyes rash Without antibiotic treatment, RMSF can lead to health[kidshealth.org]
Myalgia
  • The combination of fever, headache, myalgias, marked left shift in the differential white blood cell count, severe thrombocytopenia, and hyponatremia all help to suggest the correct diagnosis early in the course of the illness.[ncbi.nlm.nih.gov]
  • Abstract Initial symptoms of Rocky Mountain spotted fever (RMSF), a tick-borne illness caused by Rickettsia rickettsii, are nonspecific and include headache, gastrointestinal disturbances, malaise, and myalgias, followed by fever and rash.[ncbi.nlm.nih.gov]
  • All patients initially had several nonspecific signs and symptoms, including fever, headache, nausea, vomiting, or myalgia, but deteriorated rapidly without receipt of a tetracycline-class antimicrobial drug.[ncbi.nlm.nih.gov]
  • Symptoms can include fever, headache, photophobia, malaise, myalgias, and a petechial rash that begins on the wrists and ankles and spreads to the trunk.[ncbi.nlm.nih.gov]
  • The abrupt onset of the disease includes severe headache, fever, chills, arthralgia, and myalgia. After 2–3 days of these constitutional symptoms, erythematous macules erupt on the wrists, hands, forearms, legs, and ankles, as seen in these figures.[webmd.com]
Arthralgia
  • The abrupt onset of the disease includes severe headache, fever, chills, arthralgia, and myalgia. After 2–3 days of these constitutional symptoms, erythematous macules erupt on the wrists, hands, forearms, legs, and ankles, as seen in these figures.[webmd.com]
  • The early phase symptoms include a fever, headache, malaise, myalgias, arthralgias, and nausea with or without vomiting.[aocd.org]
  • Dengue fever , also known as "breakbone fever," has severe arthralgias. Vasculitis is marked by palpable purpura rather than petechiae. Drug eruptions will have a history of exposure.[visualdx.com]
  • Symptoms of RMSF include fever, malaise, headache, myalgias and arthralgias, abdominal pain, nausea/vomiting, and photophobia.[neurology.org]
Back Pain
  • Four days later, she was treated by a chiropractor for neck and back pain, without relief. The next day she was hospitalized for further evaluation and treatment.[dx.doi.org]
Eruptions
  • We discuss the case of a patient treated with an anti-TNF-alpha inhibitor for rheumatoid arthritis who later developed a generalized erythematous macular eruption accompanied by fever.[ncbi.nlm.nih.gov]
  • RESULTS: Fifty-eight children who received an average of 1.8 courses of doxycycline before 8 years of age and who now had exposed permanent teeth erupted were compared with 213 children who had never received doxycycline.[ncbi.nlm.nih.gov]
  • Definition of Rocky Mountain spotted fever : an acute disease that is characterized by chills, fever, prostration, pains in muscles and joints, and a red to purple eruption and that is caused by a rickettsial bacteria ( Rickettsia rickettsii ) usually[merriam-webster.com]
  • Some patients may suddenly develop a petechial rash without a prior maculopapular eruption.[aocd.org]
  • After 2–3 days of these constitutional symptoms, erythematous macules erupt on the wrists, hands, forearms, legs, and ankles, as seen in these figures. Lesions then spread to the palms and soles and the trunk.[webmd.com]
Petechiae
  • Areas of petechiae may result in tiny scars. In rare cases, severe necrosis and gangrene may require amputation.[dermnetnz.org]
  • Vasculitis is marked by palpable purpura rather than petechiae. Drug eruptions will have a history of exposure. Secondary syphilis can also present with a palm and sole rash; occasionally, the rash imparts a rust-colored hue.[visualdx.com]
  • He had a third heart sound, enlarged liver, and diffuse petechiae ( figure, A ). The remaining examination was unremarkable.[neurology.org]
  • As illness progresses, the rash can develop associated petechiae (days 5-6). Triad of Fever, Rash, and Tick Exposure is not commonly seen initially. 50% have a rash present within first 3 days of illness.[pedemmorsels.com]
  • The lesions eventually become raised (papular) and darker and may develop reddish spots (petechia) due to small areas of abnormal bleeding (hemorrhages).[rarediseases.org]
Maculopapular Rash
  • The woman presented with a fever followed by respiratory distress, maculopapular rash, and an eschar at the site from which a tick had been removed. She died four days after disease onset.[ncbi.nlm.nih.gov]
  • rash appears rash may lead to cutaneous necrosis altered mental status and/or coma may be observed in late stages Evaluation Diagnosis is primarily clinical based on fever, rash, and history of tick exposure Indirect immunoflourescence of skin biopsy[medbullets.com]
  • The classic maculopapular rash on the back of a patient with RMSF (from Google images). -- Figure 1, left - The Rocky Mountain Wood Tick (Dermacentor andersoni ) right - The American Dog Tick (Dermacentor vari-abilis ) (images from CDC website).[propath.org]
  • Initial symptoms: Fever Nausea Emesis (vomiting) Severe headache Muscle pain Lack of appetite Parotitis in some cases (somewhat rare)Later signs and symptoms: Maculopapular rash Petechial rash Abdominal pain Joint pain Conjunctivitis ForgetfulnessThe[en.wikipedia.org]
  • An 11-year-old white female resident of Cape Girardeau County presented in late May with a low-grade fever at home (in-office temperature, 38.3 C), frontal headache, stomachache, and an erythematous maculopapular rash on her arms, legs, and trunk that[dx.doi.org]
Purpura
  • Abstract A patient presented with findings compatible with thrombotic thrombocytopenic purpura. The diagnosis of Rocky Mountain spotted fever was also considered because the patient was a hunter in a tick-infested area.[ncbi.nlm.nih.gov]
  • Idiopathic thrombocytopenic purpura (ITP) presents with a petechial rash. Thrombotic thrombocytopenic purpura (TTP) is characterized by fever, anemia, thrombocytopenia, renal impairment, and neurological deficits.[visualdx.com]
  • Meningoencephalitis Acute Renal Failure ARDS Shock Arrhythmia Cutaneous necrosis May become look similar to other conditions like Kawasaki or thrombocytopenic purpura.[ Biggs, 2016 ] Common lab abnormalities include: Thrombocytopenia (consumptive) Hyponatremia[pedemmorsels.com]
  • […] common. 1 , 3 The triad becomes apparent in 60%–70% of patients within the first 2 weeks of illness. 1 Rash typically develops between 2 and 5 days after fever, and is initially maculopapular in appearance, progressing to petechiae, or less frequently purpura[neurology.org]
  • On admission, she had petechiae in some areas and blanching erythematous papules in others, but no palpable purpura. It was unclear when her rash had developed petechial characteristics.[dx.doi.org]
Palpable Purpura
  • Vasculitis is marked by palpable purpura rather than petechiae. Drug eruptions will have a history of exposure. Secondary syphilis can also present with a palm and sole rash; occasionally, the rash imparts a rust-colored hue.[visualdx.com]
  • On admission, she had petechiae in some areas and blanching erythematous papules in others, but no palpable purpura. It was unclear when her rash had developed petechial characteristics.[dx.doi.org]
Kidney Failure
  • Untreated, the infection may lead to health problems such as: Brain damage Clotting problems Heart failure Kidney failure Lung failure Meningitis Pneumonitis (lung inflammation) Shock Call your provider if you develop symptoms after exposure to ticks[nlm.nih.gov]
  • Possible Complications Untreated, the infection may lead to health problems such as: Brain damage Clotting problems Heart failure Kidney failure Lung failure Meningitis Pneumonitis (lung inflammation) Shock When to Contact a Medical Professional Call[ufhealth.org]
  • Renal system, like loss of bladder control or kidney failure. Mortality rate depends on a series of factors, like age, race, gender and wrong diagnosis due to partial or total absence of the key RMSF features.[symptoma.com]
  • This can lead to partial paralysis *, hearing loss, meningitis *, heart failure, brain damage, kidney failure, and shock *. Dr. Ricketts Even if you have heard about Rocky Mountain spotted fever, you may not know the name Howard T. Ricketts. Dr.[humanillnesses.com]
Headache
  • Symptoms can include fever, headache, photophobia, malaise, myalgias, and a petechial rash that begins on the wrists and ankles and spreads to the trunk.[ncbi.nlm.nih.gov]
  • Most people who get sick with RMSF will have a fever, headache, and rash. RMSF can be deadly if not treated early with the right antibiotic.[cdc.gov]
Confusion
  • Abstract A 32-year-old black man from rural southeastern Texas had headache, fever, chills, bronchopneumonia, and an atypical rash, complicated by hypotension, lethargy, confusion, liver dysfunction, thrombocytopenia, and acute renal failure.[ncbi.nlm.nih.gov]
  • Abstract A patient initially presented in the emergency room with fever, confusion, and a petechial rash. Rocky Mountain Spotted Fever (RMSF) was diagnosed and appropriate treatment was initiated.[ncbi.nlm.nih.gov]
  • These manifestations could, and often did, confuse physicians seeing these patients initially. They further accounted for the diverse complications seen. Outcome was good in this series.[ncbi.nlm.nih.gov]
  • They may include: Chills and fever Confusion Headache Muscle pain Rash -- usually starts a few days after the fever; first appears on wrists and ankles as spots that are 1 to 5 mm in diameter, then spreads to most of the body.[nlm.nih.gov]
  • Thus, Rocky Mountain spotted fever is difficult to diagnose and frequently confused with other nonspecific febrile illnesses. For this reason RMSF has also been defined as the “great imitator” of other diseases.[symptoma.com]
Meningism
  • Abstract Eosinophilic meningitis was documented in a patient with Rocky Mountain spotted fever. Rickettsial disease should be considered a diagnostic possibility in patients with cerebrospinal fluid eosinophilia.[ncbi.nlm.nih.gov]
  • […] of the meninges, the membranes that surround the brain, and the spinal cord.[humanillnesses.com]
  • Untreated, the infection may lead to health problems such as: Brain damage Clotting problems Heart failure Kidney failure Lung failure Meningitis Pneumonitis (lung inflammation) Shock Call your provider if you develop symptoms after exposure to ticks[nlm.nih.gov]
  • Meningitis has prominent neurological signs. Idiopathic thrombocytopenic purpura (ITP) presents with a petechial rash.[visualdx.com]
Ataxia
  • Four weeks later, he presented to our rehabilitation unit with ataxia, hyperreflexia and upper motor neuron signs, dysesthesias, sensorimotor axonopathy demonstrated by electrodiagnostic studies, and a global decrement in cognitive capability.[ncbi.nlm.nih.gov]
  • CASE REPORT We describe an advanced case of RMSF in a 45-year-old female patient with pet dog exposure who presented with altered mental status, dyspnea, and ataxia progressing to septic shock and acute hypoxic respiratory failure requiring intubation[ncbi.nlm.nih.gov]
  • Later manifestations include rash, photophobia, confusion, ataxia, seizures, cough, dyspnea, arrhythmias, jaundice, and severe abdominal pain. Rash occurs more frequently in children and young adults than in older individuals.[visualdx.com]
  • Central nervous system manifestations include lethargy and confusion (about 25% of all cases), ataxia (18%), coma (9-10%), and seizures (8%).[columbia-lyme.org]
  • Symptoms and findings that may suggest progressively severe encephalitis may include restless, disorientation, impaired control of voluntary movements (ataxia), sudden episodes of uncontrolled electrical activity in the brain (seizures), unresponsiveness[rarediseases.org]
Altered Mental Status
  • The patient initially presented with fever, rash, and an altered mental status, and he responded to therapy with intravenous doxycycline; serological data confirmed RMSF.[ncbi.nlm.nih.gov]
  • CASE REPORT We describe an advanced case of RMSF in a 45-year-old female patient with pet dog exposure who presented with altered mental status, dyspnea, and ataxia progressing to septic shock and acute hypoxic respiratory failure requiring intubation[ncbi.nlm.nih.gov]
  • mental status and/or coma may be observed in late stages Evaluation Diagnosis is primarily clinical based on fever, rash, and history of tick exposure Indirect immunoflourescence of skin biopsy may identify pathogen Serologies may identify immune response[medbullets.com]
  • Symptoms may include: Fever Headache Rash—begins as small, flat pink spots on wrists and ankles Nausea and vomiting Abdominal pain Muscle or joint pain Lack of appetite Red eyes Light hurting the eyes Fatigue Altered mental status Severe bleeding Difficulty[cancercarewny.com]
  • CT and MRI are strongly indicated, especially for those cases showing altered mental status, together with lumbar puncture if the presence of meningitis is suspected.[symptoma.com]

Workup

The diagnosis of Rocky Mountain spotted fever is heavily based on laboratory findings, through methods like blood count (CBC), electrolytes and renal and liver function tests. CT and MRI are strongly indicated, especially for those cases showing altered mental status, together with lumbar puncture if the presence of meningitis is suspected. Chest radiography and electrocardiography are also indicated, to reveal pulmonary and myocardial complications.

Cerebrospinal Fluid Abnormality
  • Cerebrospinal fluid abnormalities, particularly leukocytosis, were the rule in those patients who underwent lumbar puncture. Neurologic sequelae occurred in several patients.[ncbi.nlm.nih.gov]
Hyponatremia
  • The combination of fever, headache, myalgias, marked left shift in the differential white blood cell count, severe thrombocytopenia, and hyponatremia all help to suggest the correct diagnosis early in the course of the illness.[ncbi.nlm.nih.gov]
  • Laboratory evaluation may demonstrate hyponatremia, anemia, thrombocytopenia, abnormal liver enzymes, and elevated coagulation tests. Antibody testing can be helpful, but these results are not typically available to the emergency clinician.[ncbi.nlm.nih.gov]
  • Rash, history of tick bite, thrombocytopenia, and hyponatremia were often absent at initial presentation. CONCLUSIONS: Earlier treatment with doxycycline can decrease morbidity and mortality from RMSF in this region.[ncbi.nlm.nih.gov]
  • Other laboratory findings that are common in advanced cases include hyponatremia, elevations in serum aminotransferases and bilirubin, azotemia, and prolongation of the partial thromboplastin and prothrombin times.[aocd.org]
  • Thrombocytopenia and hyponatremia and acute respiratory distress syndrome with organ failure may also be seen. A serious complication of RMSF is rhabdomyolysis . Long-term sequelae include central nervous system deficits and amputations.[visualdx.com]
Decreased Platelet Count
  • Age and decreased platelet count at presentation have been independently associated with the development of ARF by multivariate analysis. ARF development increases the odds ratio of dying by a factor of 17.[emedicine.com]
Rickettsia Rickettsii
  • Da Wikimedia Commons, l'archivio di file multimediali liberi Jump to navigation Jump to search Rocky Mountain spotted fever is caused by Rickettsia rickettsii, a species of bacteria that is spread to humans by hard ticks (Ixodidae).[commons.wikimedia.org]
  • rickettsii , Typhus de Sao Paulo German Rickettsia rickettsii-Infektion , Zeckenbissfieber durch Rickettsia rickettsii , Rocky-Mountain-Fleckfieber , Sao-Paulo-Typhus , Typhus, Sao-Paulo- Portuguese Infecção por Rickettsia rickettsii , Febre Maculosa[fpnotebook.com]
  • , Infezione da Rickettsia rickettsii, Febbre di Sao Paulo, Febbre maculosa delle Montagne Rocciose Dutch Rickettsia rickettsii-infectie, Rickettsia; rickettsii, spotted fever, Rocky Mountain; spotted fever, Sao Paulo; koorts, Sao Paulo; spotted fever,[fpnotebook.com]
  • Abstract Rocky Mountain spotted fever (RMSF) is a tick-borne disease caused by the obligate intracellular bacterium Rickettsia rickettsii. Although RMSF was first reported in Colombia in 1937, it remains a neglected disease.[ncbi.nlm.nih.gov]
  • Abstract Patients with Rocky Mountain spotted fever (RMSF), a tickborne infection caused by Rickettsia rickettsii, respond quickly to tetracycline-class antibiotics (e.g., doxycycline) when therapy is started within the first few days of illness; however[ncbi.nlm.nih.gov]

Treatment

Rocky Mountain spotted fever is usually treated with doxycycline-based antibiotic therapy. Treatment should be initiated immediately, without waiting for the laboratory confirmation. Preventive treatment for patients with tick bite history is not recommended, because it might only delay the disease presentation [16] and reduce the prospect of recovery. Chloramphenicol is a valid alternative to doxycycline, even though less used because of its numerous side effects.

Prognosis

The vascular inflammation triggered by Rickettsia rickettsii causes the blood vessels to leak or form clots, and the loss of fluid ultimately results in loss of circulation at the extremities of the body, which may even become paralyzed or gangrenous without prompt treatment. The disease determines a series of severe long-term health problems to the organs and tissues encountered along the way, which mainly involve the following systems:

Mortality rate depends on a series of factors, like age [7], race [8], gender and wrong diagnosis [9] [10] due to partial or total absence of the key RMSF features [7] [11]. It also seems to have significantly declined since 1980s, from 4% in 1982 to 1,4% and less in 2002 [12] [13] [14].

Etiology

Rickettsia rickettsii is an obligate intracellular parasite which thrives in the cytoplasm of its eukaryotic host cells, especially those belonging to the endothelial tissue [2]. The natural RMSP hosts are ticks of the genus Dermacentor, like Dermacentor variabilis (the American dog tick), which largely feeds on big mammals. Because of this intra-species transmission, RMSP is a classical example of zoonosis. Dog is the excellent vector for Rickettsia rickettsii, given its high susceptibility to this bacterium and its higher rate to tick exposure.

Epidemiology

Cases of RMSF have been reported in the United States since 1920’s. According to the most recent statistical data over the last decade, RMSF prevalence has increased, from an initial rate of 2 cases per million persons in 2000 to a final one of over 6 cases per million persons in 2010 [3]. By contrast, fatality has heavily declined over the same period, arriving at the current rate of 0,5% [3], perhaps as a consequence of the positive effects of better diagnostic and surveillance practices. No RMSP case has been reported outside the Americas, even though a variety of related diseases have been described in other continents. In any case, a clear picture of RMSP incidence worldwide still remains largely unknown.

Peaks of RMSP have been observed in North Carolina, Oklahoma, Arkansas, Tennessee, and Missouri, with more than the 60% of the cases reported. The peaks mostly appear in summer, between June and July, but some cases can also spring up in other months of the year. This seasonality varies from state to state, and it is strictly linked to the life cycle of the vector involved.

The persons at risk are mostly American Indians, males and people over 70 years of age [4]. Additional factors might be the exposure to dogs and wooded areas and the state of the immune system [4]. Particularly susceptible are also children under 10 years of age [3] [4] [5].

Sex distribution
Age distribution

Pathophysiology

The main site of Rickettsia rickettsii is the endothelium of blood vessels, where the bacterium easily propagates tdue to the mechanism of actin polar polymerization [6].

The endothelial cell injury triggers a series of important physiological modifications, like increased vascular permeability, edema, hypotension and hypoalbuminemia, which cause the blood vessels to become blocked and inflamed (vasculitis). This systemic vascular damage is soon followed by a series of severe complications, like interstitial pneumonia.

Prevention

RMSP prevention is very easy if a few simple precautions are followed, like wearing long pants and sleeves and using insect repellents. In the areas where RMSP cases have been reported, you are also strongly advised to tick-proof your yard and check yourself for ticks.

Summary

Rocky Mountain spotted fever (RMSP) is spread to humans by ticks. Very difficult to diagnose, especially in the early stages, its typical signs include sudden fever, headache and muscle pain. Without proper treatment, this disease may sometime be lethal [1]. Its name is a misnomer, since although very frequent in the Rocky Mountain region, where it was first recognized towards the end of the nineteenth century with the name of “black measles”, the illness has been diagnosed throughout the American continent, from as far north as Canada to as far south as Central America.

Patient Information

Rocky Mounatin spotted fever (RMSP) is an illness caused by Rickettsia rickettsii, a bacterium belonging to a group responsible for diseases such as typhus and rickettsialpox. Its natural hosts are the ticks of the species Dermacentor variabilis (the American dog tick), which largely feeds on big mammals. Once in the body, the bacterium infects the endothelium of blood vessels, causing vascular inflammation and thereby a series of severe complications, like interstitial pneumonia and a rash with the characteristic “inward” diffusion patters. The initial symptoms of fever, rush and headache are soon followed by muscle pain and other complications of key apparatuses such as the nervous and gastrointestinal systems. The RMSP is usually treated with doxycycline-based antibiotic therapy, but chloramphenicol can be a valid alternative.

References

Article

  1. Masters EJ, Olson GS, Weiner SJ, Paddock CD. Rocky Mountain spotted fever: a clinician's dilemma. Arch. Intern. Med. 2003 163 (7): 769–74
  2. Walker DH. Rickettsiae. In: Barron's Medical Microbiology (4th ed.). Galveston (TX): University of Texas Medical Branch at Galveston; 1996. Chapter 38. 
  3. Openshaw JJ, Swerdlow DL, Krebs JW, Holman RC et al.  Rocky Mountain spotted fever in the United States, 2000-2007: Interpreting contemporary increases in incidence. Am J Trop Med Hyg. 2010 Jul;83(1):174-82.
  4. Dahlgren FS, Holman RC, Paddock CD, Callinan LS, McQuiston JH. Fatal Rocky Mountain spotted fever in the United States, 1999–2007. Am J Trop Med Hyg(86)2012, 713
  5. Demma LJ, Traeger MD, Nicholson WL, Paddock CD et al. Rocky Mountain spotted fever from an unexpected tick vector in Arizona. N Engl J Med. 2005 Aug 11;353(6):587-94.
  6. Carlsson F, Brown EJ. Actin-based motility of intracellular bacteria, and polarized surface distribution of the bacterial effector molecules. J Cell Physiol. 2006 Nov; 209 (2):288-96.
  7. Holman RC, Paddock CD, Curns AT, Krebs JW, McQuiston JH, Childs JE. Analysis of risk factors for fatal Rocky Mountain spotted fever: evidence for superiority of tetracyclines for therapy. J Infect Dis. 2001; 184:1437-1444.
  8. Helmick CG, Bernard KW, D'Angelo LJ. Rocky Mountain spotted fever: clinical, laboratory, and epidemiological features of 262 cases. J Infect Dis. 1984;150:480-488.
  9. Buckingham SC, Marshall GS, Schutze GE, Woods CR et al. Clinical and laboratory features, hospital course, and outcome of Rocky Mountain spotted fever in children. J Pediatr. 2007;150:180-184.
  10. Chapman AS, Bakken JS, Folk SM, Paddock et al. Diagnosis and management of tickborne rickettsial diseases: Rocky Mountain spotted fever, ehrlichioses, and anaplasmosis--United States: a practical guide for physicians and other health-care and public health professionals. MMWR Recomm Rep. 2006;55:1-27.
  11. Hattwick MA, Retailliau H, O'Brien RJ, Slutzker M, Fontaine RE, Hanson B.Fatal Rocky Mountain spotted fever. JAMA. 1978;240:1499-1503.
  12. Treadwell TA, Holman RC, Clarke MJ, Krebs JW, Paddock CD, Childs JE. Rocky Mountain spotted fever in the United States, 1993-1996. Am J Trop Med Hyg. 2000;63:21-26.
  13.  Dalton MJ, Clarke MJ, Holman RC, Krebs JW et al. National surveillance for Rocky Mountain spotted fever, 1981-1992: epidemiologic summary and evaluation of risk factors for fatal outcome. Am J Trop Med Hyg. 1995;52:405-413.
  14. Chapman AS, Murphy SM, Demma LJ, Holman RC et al. Rocky Mountain spotted fever in the United States, 1997-2002. Vector Borne Zoonotic Dis. 2006;6:170-178.
  15. Sexton DJ, Corey GR. Rocky Mountain "spotless" and "almost spotless" fever: a wolf in sheep's clothing.Clin Infect Dis. Sep 1992;15(3):439-48
  16. Gammons M, Salam G. Tick removal. Am Fam Physician 2002 66 (4): 643–5. 

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Last updated: 2018-06-21 20:09