Anthrax or splenic fever, as it was formerly called, is an infectious disease caused by Bacillus anthracis, a Gram-positive, rod-shaped bacterium. It mainly affects herbivores and infected animals may serve as a source of infection for humans, rendering anthrax a zoonotic disease. In recent years, the disease has attracted considerable attention as a potential bioterrorist threat. Clinically, there are three types of anthrax: cutaneous, gastrointestinal and inhalational. Initial symptoms differ between those variants of the disease, but all may lead to sepsis and death if not treated accordingly.
Presentation
Depending on the port of entry, inhalational, gastrointestinal, or cutaneous anthrax may be developed. Some authors also describe a fourth form of the disease, namely injectional anthrax [1].
The classical variants of anthrax manifest as follows [2]:
- Contrary to other forms of splenic fever, inhalational anthrax is not characterized by local disease before systemic spread. From the lungs, bacteria reach regional lymph nodes and the bloodstream. Non-specific symptoms like malaise, fatigue, fever, chills, dyspnea and non-productive cough, nausea and vomiting may precede the acute phase of the disease [3]. The latter is marked by sudden dyspnea, cyanosis, coma and death.
- The ingestion of Bacillus anthracis spores may lead to oropharyngeal or, more commonly, to gastrointestinal anthrax. In case of oropharyngeal anthrax, an initial lesion that may measure several centimeters in diameter can be observed in the oral cavity or pharyngeal mucosa. This lesion is usually covered by a pseudomembrane, frequently ulcerates and is surrounded by extensive edema. It causes dysphagia and may be associated with regional lymphadenopathy [4]. Similarly to oropharyngeal anthrax, ulcerative lesions may be encountered in other parts of the gastrointestinal tract, and this condition is known as gastrointestinal anthrax. Hemorrhages from such lesions may be profound and provoke hemodynamic failure. Gastrointestinal perforation is another dreaded complication of this form of splenic fever. It is accompanied by unspecific symptoms like fever, nausea, vomiting, diarrhea, and abdominal pain, that frequently don't raise suspicion for anthrax, but rapidly develop into hematemesis, bloody diarrhea, and severe ascites [4].
- Cutaneous anthrax manifests up to three days after the inoculation of the pathogen in form of a single papule, less frequently of multiple skin lesions. Subsequently, vesicles develop around that papule and fluid builds up in the surrounding skin. Regional lymphadenopathy may be noted at this point, but otherwise neither pain nor pus are reported. During the following days, ulceration occurs and eschar forms, and associated edema may expand to adjacent body regions and exert mass-like effects that may require emergency procedures. Patients presenting with anthrax eschar frequently claim constitutional symptoms like malaise, fever, and headaches, too. If the disease takes a self-limiting course, skin lesions start to resolve about one week after the initial appearance of the papule.
Anthrax meningitis may complicate any of the aforementioned variants of the disease. Patients developing anthrax meningitis suffer from high-grade fever, changes of their mental state, neck pain, and vomiting. All forms of anthrax may eventually give rise to toxemia, bacteremia, septicemia, septic shock, coma and death. Mortality is significantly higher, though, in pulmonary and gastrointestinal splenic fever than in cutaneous anthrax.
Immune System
- Cervical Lymphadenopathy
In oro-oesophageal anthrax, the clinical manifestations include sore throat, dysphagia, fever, cervical lymphadenopathy, and oedema. [pubmedcentral.nih.gov]
Most patients presented with fever and neck swelling secondary to cervical lymphadenopathy. Initial ulcers were associated with congestion, followed by central necrosis, whitish discoloration, and eventually a pseudomembranous covering. [atsjournals.org]
Entire Body System
- Fever
Gastrointestinal perforation is another dreaded complication of this form of splenic fever. [symptoma.com]
Clinical Mediastinal widening, pleural effusions, fever, nonproductive cough, myalgia, malaise, haemorrhage, cyanosis, SOB, stridor, shock, death; often accompanied by mesenteric lymphadenitis, diffuse abdominal pain and fever. [medical-dictionary.thefreedictionary.com]
These symptoms can occur within 7 days of infection: Fever (temperature greater than 100 degrees F). The fever may be accompanied by chills or night sweats. [web.archive.org]
The former was admitted to the hospital with complaints of headache, vomiting, fever, and decreased level of consciousness. The latter presented with abdominal pain and distension, vomiting, and fever. Both cases were proven by animal inoculation. [ncbi.nlm.nih.gov]
Ingestion by eating undercooked meat of infected animals causing nausea, fever, chills, stomach pain, bloody diarrhea, and vomiting blood. Inhalation where a person develops flu like symptoms which may lead to a sore throat, fever, and muscle aches. [iamat.org]
- Malaise
Patients presenting with anthrax eschar frequently claim constitutional symptoms like malaise, fever, and headaches, too. [symptoma.com]
By comparison, “Monster at the End”, “Suzerain”, and “Defend/Avenge” are lean and muscular, the playing tight and sensational, but the progression of the songs themselves is a dulling malaise of verse-chorus-verse with a solo thrown in that grows weary [consequenceofsound.net]
Within a few days after the initial exposure, cold-like symptoms including fever, cough, aches, and general malaise develop. Although some people experience a brief recovery, this is followed by a rapid onset of more serious symptoms. [msdmanuals.com]
Initial symptoms after inhalation might include mild fever, malaise, fatigue, coughing and, occasionally a feeling of pressure on the chest. [news.bbc.co.uk]
- Fatigue
Inhalation anthrax begins with flulike symptoms, namely fever, fatigue, headache, muscle aches, and shortness of breath. [medical-dictionary.thefreedictionary.com]
More severe symptoms include a cough, shortness of breath, fatigue, and may progress to shock which can be fatal. Seek medical attention immediately if you suspect exposure to Anthrax. Treatment includes antibiotics. [iamat.org]
Non-specific symptoms like malaise, fatigue, fever, chills, dyspnea and non-productive cough, nausea and vomiting may precede the acute phase of the disease. The latter is marked by sudden dyspnea, cyanosis, coma and death. [symptoma.com]
If the Bacillus anthracis spores are inhaled, the initial signs of disease are usually flu-like symptoms including fever, sore throat, feeling unwell, body aches, fatigue, cough and chest discomfort. [ccohs.ca]
[…] rare acute systemic infection caused by the inhalation of Bacillus anthracis spores (e.g. through infected animal products, bioterrorism) and characterized by an initial stage where patients present with non specific symptoms (fever, cough, chills, fatigue [orpha.net]
- Pathologist
The Investigation Finally, in 1992, after collapse of the Soviet Union, a group of scientists, including pathologists and epidemiologists, was allowed to visit Sverdlovsk to perform an on-site investigation. [web.archive.org]
Yet neither the clinicians nor the pathologists had identified the cause of the epidemic. Moreover, as you can imagine, the members of the pathology department were frustrated and overburdened with work. So, on this day, Dr. [medicinenet.com]
Journal of clinical pathology : JCP ; the journal of the Association of Clinical Pathologists London : BMJ Publ. [zdb-katalog.de]
The organs or tumors were postfixed for 24 h in 4% (wt/vol) paraformaldehyde, embedded in paraffin, sectioned, stained with hematoxylin/eosin, and subjected to microscopic analysis by a pathologist unaware of treatment or animal genotype (two to eight [doi.org]
- Anorexia
Signs may include fever, chills, severe colic, anorexia, depression, weakness, bloody diarrhea, and swellings of the neck, sternum, lower abdomen, and external genitalia. Death usually occurs within 2–3 days of onset. [merckvetmanual.com]
The symptoms for intestinal infection include fever, nausea, abdominal pain, vomiting, and anorexia. [rarediseases.org]
Gastrointestinal anthrax presents with severe abdominal pain, fever, fatigue, anorexia, hematemesis, and bloody diarrhea. In some cases there may be lesions in the nose, mouth, and throat. [medical-dictionary.thefreedictionary.com]
Respiratoric
- Sore Throat
Inhalation anthrax: Initial symptoms may resemble a common cold – sore throat, mild fever, muscle aches and malaise. After several days, the symptoms may progress to severe breathing problems and shock. Inhalation anthrax is usually fatal. [web.archive.org]
The chances that your sore throat and aching muscles are due to anthrax are extremely small. [mayoclinic.org]
Inhalation where a person develops flu like symptoms which may lead to a sore throat, fever, and muscle aches. More severe symptoms include a cough, shortness of breath, fatigue, and may progress to shock which can be fatal. [iamat.org]
Initially, there is a flu-like illness with a nonproductive nausea, vomiting, sore throat, cough, sweats, fever, confusion, headache and myalgia. [patient.info]
- Pleural Effusion
Of these, 127 control subjects (67.6%) had infiltrates, 43 control subjects (22.9%) had pleural effusions, and 15 control subjects (8.0%) had mediastinal widening. [citeseerx.ist.psu.edu]
If inhalation anthrax is suspected, chest X-rays or CT scans can confirm if the patient has mediastinal widening or pleural effusion, which are X-ray findings typically seen in patients with inhalation anthrax. [cdc.gov]
Patients with pleural effusion benefit from drainage of the effusion with a chest tube. Patient care Health supervision is provided to at-risk employees, along with prompt medical care of all lesions. [medical-dictionary.thefreedictionary.com]
Radiographs obtained in this stage typically show pulmonary infiltrates, pleural effusion and mediastinal widening and lymphadenopathy. [symptoma.com]
- Dyspnea
Non-specific symptoms like malaise, fatigue, fever, chills, dyspnea and non-productive cough, nausea and vomiting may precede the acute phase of the disease. The latter is marked by sudden dyspnea, cyanosis, coma and death. [symptoma.com]
ہیں Multiple Word Search Search Result for inhalation anthrax Definitions English definition for inhalation anthrax 1. n. a form of anthrax infection acquired by inhalation of dust containing Bacillus anthracis; initial symptoms (chill and cough and dyspnea [ijunoon.com]
A blind 65-year-old man, living in a rural area, was admitted with respiratory infection, fever, dyspnea, loss of appetite, and myalgia. The patient was treated with outpatient antibiotics a week ago. [ncbi.nlm.nih.gov]
[…] inhalation anthrax, pulmonary anthrax, ragpicker's disease, ragsorter's disease, woolsorter's disease, woolsorter's pneumonia a form of anthrax infection acquired by inhalation of dust containing Bacillus anthracis; initial symptoms (chill and cough and dyspnea [vocabulary.com]
[…] prodrome of fever, chills, nonproductive cough, chest pain, headache, myalgias, and malaise, with more distinctive clinical hallmarks of hemorrhagic mediastinal lymphadenitis, hemorrhagic pleural effusions, bacteremia and toxemia resulting in severe dyspnea [web.archive.org]
- Respiratory Distress
Abstract A 10-year-old boy presented with facial swelling, thick exudates in the nasal cavities with membranes covering the nasopharynx, shock and respiratory distress. X-ray of the paranasal sinuses showed opacification of both maxillary sinuses. [ncbi.nlm.nih.gov]
The second stage of the disease is characterized by high fever, respiratory distress, and shock. Pleural effusion and a widened mediastinum may be evident on chest radiographs. [avma.org]
Symptoms progress to respiratory distress with stridor (vibrating noise when breathing), hypoxemia and cyanosis (bluish coloring of the skin due to low oxygen). Death from inhalation anthrax can be greater than 85% if left untreated. [health.hawaii.gov]
This is followed within 3–6 days by rapid onset of respiratory distress, including stridor, severe dyspnoea, hypoxia, shock and cyanosis, with radiological evidence of mediastinal widening. Death follows shortly thereafter. [www2.health.vic.gov.au]
- Dry Cough
In such cases the main clinical signs are: high temperature, shivering or twitching harsh dry cough blood in dung or in nostrils decrease or complete loss of milk fits bright staring eyes colicky pains dejection and loss of appetite In pigs and horses [gov.uk]
Initially, they are vague and similar to those of influenza, with mild muscle aches, a low fever, chest discomfort, and a dry cough. [merckmanuals.com]
He had a mild sore throat and occasional dry cough. [cdc.gov]
Inhalational anthrax typically begins with one to three days of fatigue, low-grade fever, and dry cough. [rarediseases.org]
Gastrointestinal
- Vomiting
Non-specific symptoms like malaise, fatigue, fever, chills, dyspnea and non-productive cough, nausea and vomiting may precede the acute phase of the disease. The latter is marked by sudden dyspnea, cyanosis, coma and death. [symptoma.com]
The former was admitted to the hospital with complaints of headache, vomiting, fever, and decreased level of consciousness. The latter presented with abdominal pain and distension, vomiting, and fever. Both cases were proven by animal inoculation. [ncbi.nlm.nih.gov]
The first signs of the disease are nausea and vomiting, loss of appetite, and fever, followed by abdominal pain, vomiting of blood, and severe bloody diarrhea. [medical-dictionary.thefreedictionary.com]
There may be fever, headache, muscle ache, vomiting and regional lymphadenopathy. The disease can be readily cured with appropriate treatment. Inhalation anthrax: It is the most severe form of anthrax. [chp.gov.hk]
- Nausea
Non-specific symptoms like malaise, fatigue, fever, chills, dyspnea and non-productive cough, nausea and vomiting may precede the acute phase of the disease. The latter is marked by sudden dyspnea, cyanosis, coma and death. [symptoma.com]
Hours after receiving dose 3 he experienced fever, chills, nausea, vomiting, and neck, hand, and shoulder pain. The vaccination series was terminated after the third dose. [ncbi.nlm.nih.gov]
Ingestion by eating undercooked meat of infected animals causing nausea, fever, chills, stomach pain, bloody diarrhea, and vomiting blood. Inhalation where a person develops flu like symptoms which may lead to a sore throat, fever, and muscle aches. [iamat.org]
The symptoms of gastrointestinal anthrax are: abdominal pain and swelling diarrhea fainting fever and chills flushing face and red eyes headache loss of appetite nausea and vomiting sore throat with painful swallowing swelling of neck and neck glands [medicalnewstoday.com]
- Abdominal Pain
The latter presented with abdominal pain and distension, vomiting, and fever. Both cases were proven by animal inoculation. [ncbi.nlm.nih.gov]
The first signs of the disease are nausea and vomiting, loss of appetite, and fever, followed by abdominal pain, vomiting of blood, and severe bloody diarrhea. [medical-dictionary.thefreedictionary.com]
It is accompanied by unspecific symptoms like fever, nausea, vomiting, diarrhea, and abdominal pain, that frequently don't raise suspicion for anthrax, but rapidly develop into hematemesis, bloody diarrhea, and severe ascites. [symptoma.com]
- Dysphagia
It causes dysphagia and may be associated with regional lymphadenopathy. Similarly to oropharyngeal anthrax, ulcerative lesions may be encountered in other parts of the gastrointestinal tract, and this condition is known as gastrointestinal anthrax. [symptoma.com]
In oropharyngeal anthrax, fever, neck swelling due to lymphadenopathy, throat pain, oral ulcers and dysphagia may be followed by severe local ulcers and swelling, septicaemia and death. [www2.health.vic.gov.au]
Symptoms include hoarseness, sore throat, fever, and dysphagia. Airway obstruction may occur. Inhalation anthrax begins insidiously as a flu-like illness. [merckmanuals.com]
Clinical Cervical oedema, lymphadenopathy (causing dysphagia), respiratory difficulty. Anthrax meningitis A rare, usually fatal complication of GI or inhalation anthrax, with death occurring 1 to 6 days after onset of illness. [medical-dictionary.thefreedictionary.com]
Symptoms for oropharyngeal illness may include fever, sore throat, difficulty in swallowing (dysphagia), collection of fluid (edema) in the tissues of the throat, and swelling of the lymph nodes. [rarediseases.org]
- Hematemesis
Neither had abdominal pain, tenderness, diarrhea, hematemesis, melena, or other expected signs and symptoms of anthrax. [ncbi.nlm.nih.gov]
[…] hypoxia and septic shock; gastrointestinal anthrax may result in pharyngeal lesions with sore throat, dypshagia marked neck swelling and regional lymphadenopathy, or intestinal infection characterized by fever, severe abdominal pain, massive ascites, hematemesis [web.archive.org]
It is accompanied by unspecific symptoms like fever, nausea, vomiting, diarrhea, and abdominal pain, that frequently don't raise suspicion for anthrax, but rapidly develop into hematemesis, bloody diarrhea, and severe ascites. [symptoma.com]
Gastrointestinal anthrax presents with severe abdominal pain, fever, fatigue, anorexia, hematemesis, and bloody diarrhea. In some cases there may be lesions in the nose, mouth, and throat. [medical-dictionary.thefreedictionary.com]
There may also be evidence for GI hemorrhage, with hematemesis, melena, or hematochezia. A notable feature of GI anthrax is the development of ascites, sometimes in massive quantities. [infectiousdiseaseadvisor.com]
Cardiovascular
- Chest Pain
Symptoms include bumps and blisters (after skin contact), difficulty breathing and chest pain (after inhaling spores), and abdominal pain and bloody diarrhea (after eating contaminated meat). [msdmanuals.com]
Cutaneous anthrax begins as a pruritic papule or vesicle that enlarges and erodes (1-2 days) leaving a necrotic ulcer with subsequent formation of a central black eschar; inhalation anthrax may begin as a prodrome of fever, chills, nonproductive cough, chest [web.archive.org]
Inhalational Anthrax Early symptoms: Cold or flu-like illness Fever Aches Sore throat Later symptoms: Cough Chest pain Shortness of breath Gastrointestinal Anthrax Fever Nausea Decreased appetite Diarrhea, usually bloody Abdominal pain Self-Care Guidelines [skinsight.com]
- Cyanosis
Later symptoms include an abrupt onset of a high fever and severe respiratory distress (cyanosis, dyspnea, stridor). Treatment is a 60-day course of antibiotics such as ciprofloxacin, levofloxacin, doxycycline, and penicillin. [medical-dictionary.thefreedictionary.com]
Patients also develop pallor or cyanosis, dyspnoea, tachycardia, abdominal pain and pleuritic chest pain. Abrupt onset of respiratory failure may develop 2-4 days later. [patient.info]
The latter is marked by sudden dyspnea, cyanosis, coma and death. The ingestion of Bacillus anthracis spores may lead to oropharyngeal or, more commonly, to gastrointestinal anthrax. [symptoma.com]
Symptoms progress to respiratory distress with stridor (vibrating noise when breathing), hypoxemia and cyanosis (bluish coloring of the skin due to low oxygen). Death from inhalation anthrax can be greater than 85% if left untreated. [health.hawaii.gov]
Eyes
- Visual Impairment
If patients experience visual impairment, prompt ophthalmic evaluation is recommended. If patients have contraindications to linezolid use or it is unavailable, clindamycin is an acceptable alternative. [doi.org]
Skin
- Skin Lesion
B. anthracis can be cultured from blood, ascitic fluid, cerebrospinal fluid, pleural effusion or skin lesion. Blood culture is almost always positive. Culture of skin lesion is positive in only 60-65% of cases. [patient.info]
"dark skin lesion, carbuncle," going back to Middle French antrac, borrowed from Late Latin anthrac-, anthrax, borrowed from Greek anthrak-, ánthrax "charcoal (burning or unlit, usually in plural), coal, dark red precious stone, dark skin lesion," probably [merriam-webster.com]
Cutaneous anthrax manifests up to three days after the inoculation of the pathogen in form of a single papule, less frequently of multiple skin lesions. Subsequently, vesicles develop around that papule and fluid builds up in the surrounding skin. [symptoma.com]
After isolation of the Gram-positive bacilli from the skin lesions, prompt antibiotic treatment (intravenous sulbactam-ampicillin 1.5 g every six hours) was initiated. [ncbi.nlm.nih.gov]
- Skin Ulcer
Anthrax infection can be contracted through: Skin lesions where the bacteria invade the blood stream and cause blisters and a skin ulcer characterized by dying skin (black area) in the center. [iamat.org]
Symptoms of anthrax exposure include skin ulcers, nausea, vomiting and fever, and can cause death if untreated. The military has ordered all of its labs that have previously received inactive anthrax samples to test them. [bbc.com]
The blister then develops into a skin ulcer with a black area in the center. The affected area does not usually hurt. [vdh.virginia.gov]
The blister then becomes a skin ulcer with a black area in the center. (The sore, blister and ulcer do not hurt.) Patients also may have fever, malaise and headaches. [idph.state.il.us]
A skin ulcer may be biopsied. If your doctor thinks that you have inhalational anthrax, you may have a chest X-ray or a CT scan. How is it treated? Antibiotics are used to treat all types of anthrax. [healthy.kaiserpermanente.org]
- Skin Edema
/ Integumentary Signs / Alopecia, thinning, shedding, easily epilated, loss of, hair Sign Skin / Integumentary Signs / Moist skin, hair or feathers Sign Skin / Integumentary Signs / Skin edema Cattle & Buffaloes:All Stages,Other:All Stages,Sheep & Goats [cabi.org]
Face, Head & Neck
- Neck Swelling
swelling and regional lymphadenopathy, or intestinal infection characterized by fever, severe abdominal pain, massive ascites, hematemesis, and bloody diarrhea. [web.archive.org]
In oropharyngeal anthrax, fever, neck swelling due to lymphadenopathy, throat pain, oral ulcers and dysphagia may be followed by severe local ulcers and swelling, septicaemia and death. [www2.health.vic.gov.au]
Gastrointestinal Typically 1 to 6 days following exposure Oropharyngeal: Symptoms are fever, ulcers in the back of the mouth and throat, severe sore throat, difficulty swallowing, and lymph node and neck swelling. [centerforhealthsecurity.org]
Most patients presented with fever and neck swelling secondary to cervical lymphadenopathy. Initial ulcers were associated with congestion, followed by central necrosis, whitish discoloration, and eventually a pseudomembranous covering. [atsjournals.org]
Pigs, carnivores, and primates: Local oedemas and swelling of the face and neck or of lymph nodes, particularly mandibular, pharyngeal and/or mesenteric. [cabi.org]
Neurologic
- Headache
The former was admitted to the hospital with complaints of headache, vomiting, fever, and decreased level of consciousness. The latter presented with abdominal pain and distension, vomiting, and fever. Both cases were proven by animal inoculation. [ncbi.nlm.nih.gov]
They found a number of local and systemic reactions, including swelling at the injection site (up to 10cm in diameter), muscle aches, headaches, and mild-to-moderate malaise. [thinktwice.com]
Inhalation anthrax begins with flulike symptoms, namely fever, fatigue, headache, muscle aches, and shortness of breath. [medical-dictionary.thefreedictionary.com]
Initially, there is a flu-like illness with a nonproductive nausea, vomiting, sore throat, cough, sweats, fever, confusion, headache and myalgia. [patient.info]
Workup
Anamnestic data are of major importance in the workup of anthrax cases: Specific symptoms are rare and the confirmation of exposure to livestock or animal products may be one of very view hints on an infection with Bacillus anthracis. A reliable diagnosis of anthrax requires the identification of the etiologic pathogen or its toxins, either by means of conventional techniques (microscopic examination, Gram stain, culture) or molecular biological approach [5]. Samples may consist in fluid specimens of pulmonary or pleural effusion or serum, or may be obtained by means of bronchial biopsy, using oropharyngeal or wound swabs. It should be noted that treatment with antibiotics negatively affects the sensitivity of any method applied to isolate the causative bacterium [2].
In case of inhalational anthrax, chest radiographs may provide vital information before the onset of the acute phase of the disease. Radiographs obtained in this stage typically show pulmonary infiltrates, pleural effusion and mediastinal widening and lymphadenopathy [2]. However, computer tomography is considered more sensitive with regards to the detection of mediastinal lymph node involvement than radiography, and this finding is much more specific for anthrax than mediastinal widening.
Microbiology
- Gram-Positive Rods
Bacillus anthracis, the causal agent in anthrax, is a Gram-positive rod. Humans can acquire anthrax by industrial exposure to infected animals or animal products. [ncbi.nlm.nih.gov]
Anthrax is a serious infectious disease caused by gram-positive, rod-shaped bacteria known as Bacillus anthracis. Although it is rare, people can get sick with anthrax if they come in contact with infected animals or contaminated animal products. [cdc.gov]
Anthrax is a serious infectious disease caused by gram-positive, rod-shaped bacteria known as Bacillus anthracis. Anthrax can be found naturally in soil and commonly affects domestic and wild animals around the world. [web.archive.org]
Anthrax or splenic fever, as it was formerly called, is an infectious disease caused by Bacillus anthracis, a Gram-positive, rod-shaped bacterium. [symptoma.com]
rod-shaped bacteria known as Bacillus anthracis. [health.mil]
Pleura
- Pleural Effusion
Of these, 127 control subjects (67.6%) had infiltrates, 43 control subjects (22.9%) had pleural effusions, and 15 control subjects (8.0%) had mediastinal widening. [citeseerx.ist.psu.edu]
If inhalation anthrax is suspected, chest X-rays or CT scans can confirm if the patient has mediastinal widening or pleural effusion, which are X-ray findings typically seen in patients with inhalation anthrax. [cdc.gov]
Patients with pleural effusion benefit from drainage of the effusion with a chest tube. Patient care Health supervision is provided to at-risk employees, along with prompt medical care of all lesions. [medical-dictionary.thefreedictionary.com]
Radiographs obtained in this stage typically show pulmonary infiltrates, pleural effusion and mediastinal widening and lymphadenopathy. [symptoma.com]
Treatment
In the United States, the Centers for Disease Control and Prevention published the following guidelines on the clinical management of anthrax [6]:
- Intravenous application of at least one bactericidal agent and one protein synthesis inhibitor is recommended without exception in patients suffering from systemic disease. In case of anthrax meningitis, another bactericidal agent should be added.
- Patients with anthrax meningitis should receive antibiotics able to penetrate into the central nervous system, e.g., β-lactam antibiotics, carbapenems, quinolones, or vancomycin. In most parts of the world, penicillin G is the drug of choice for anthrax treatment irrespective of whether or not the patient suffers from anthrax meningitis. Bacillus anthracis may show resistance against β-lactam antibiotics, though [7]. Resistances against other types of antibiotics have also been reported [8].
- Linezolid is preferred over other protein synthesis inhibitors, but clindamycin and rifampin are valuable alternatives. Chloramphenicol and doxycycline may also be applied.
- System anthrax requires treatment for at least two weeks.
- Oral monotherapy may suffice to treat cutaneous anthrax, but recommendations as given above should be followed in patients showing severe edema or systemic symptoms.
Some patients have been applied corticosteroids in an attempt to reduce anthrax-associated edema. However, conclusive results as to the efficacy of such an approach have not yet been presented.
Prognosis
If left untreated, all forms of anthrax are potentially life-threatening. However, self-limiting courses are regularly observed in cases of cutaneous anthrax. All possible measures should be taken to assure an early diagnosis and timely initiation of treatment, since progression from local disease to sepsis rapidly ensues death.
Etiology
Anthrax is caused by Bacillus anthracis, a Gram-positive, rod-shaped, obligate pathogen. Bacillus anthracis may be encountered in its vegetative form or in form of spores. The disease is most commonly contracted by the inhalation, oral uptake or cutaneous inoculation of spores [2]. Of note, those spores are extremely resistant to heat, pressure, ultraviolet and ionizing radiation, chemical agents and disinfectants and may survive for decades in soil, i.e., long periods of time may pass between outbreaks [9]. Within the host - either the animal or a human being - the spores germinate, which gives rises to vegetative state Bacillus anthracis that releases three proteins that form two toxins, as described below.
Epidemiology
Anthrax endemic regions comprise the Middle East, West Africa, Central Asia, parts of India, and South America, but outbreaks may occur anywhere even though some countries claim freedom of splenic fever [9]. Indeed, outbreaks have recently been reported in different parts of Europe [10] [11]. Because the disease primarily affects herbivores, people with occupational exposure to susceptible animals like cattle and sheep, but also goats and horses, have a greater risk of contracting anthrax. Similarly, those working with contaminated animal products are more likely to become infected. The overall risk of human-to-human-transmission is considered to be close to cero [2].
In humans, individuals of any age and both genders are affected equally.
Pathophysiology
The vast majority of infections with Bacillus anthracis is contracted by inhalation, oral ingestion or cutaneous inoculation of the pathogen [2]:
- For anthrax to develop upon the inhalation of spores, large quantities of spores have to be inhaled. Even in the unlikely scenario of Bacillus anthracis being used in a bioterrorist attack, the overall likelihood of pulmonary infections remains low.
- The oral ingestion of the causative pathogen is more commonly observed where people use to consume undercooked meat, e.g., in Sub-Saharan Africa and South East Asia.
- Even though the infectious dose for cutaneous anthrax is considered to be very low, the pathogen is presumably non-invasive, only being able to pass the skin barrier via epidermal lesions. However, such ports of entry cannot be identified in all patients suffering from cutaneous anthrax.
Bacillus anthracis has two major virulence factors: anthrax toxins and an antiphagocytic polyglutamic capsule [12]. In early stages of the infection, anthrax toxins presumably target immune cells like dendritic cells, macrophages and neutrophils, interfere with chemotaxis, release of chemokines, cytokines and reactive oxygen species, among others, and even induce cell death. The pathogen's antiphagocytic capsule also contributes to the evasion of the innate immune response. In sum, both anthrax toxins and capsule largely facilitate pathogen survival at the port of entry and allow for the subsequent dissemination of Bacillus anthracis. In late stages of the disease, anthrax toxins mediate possibly highly life-threatening effects on the cardiovascular system and most likely a variety of other organ systems [1].
Prevention
In 1970, the Anthrax Vaccine Adsorbed has been licensed in the United States. It was initially used to protect those at greater risk due to possible occupational exposure, but may also be applied to immunize military personnel and anyone else considered to be at risk in a specific situation. The vaccine has been proven to be safe and effective [13]. Ongoing research aims at producing better defined vaccines in more convenient formulations and presentations [1].
On the other hand, both antibiotic treatment and vaccination are effective measures in controlling anthrax outbreaks in animals. Infected animals usually respond favorably to antimicrobial therapy and even if its survival cannot be achieved, pathogen loads are significantly reduced.
Summary
Anthrax is an infectious disease usually affecting cattle and sheep or other livestock [14]. People who work with infected animals or contaminated animal products are at risk of inhaling spores of the causative pathogen, Bacillus anthracis. This bacterium may also enter into the human body via skin lesions or upon the ingestion of contaminated, undercooked food. Depending on the port of entry, patients may develop inhalative, cutaneous, or gastrointestinal anthrax. While cutaneous anthrax may run a self-limiting course, all variants of the disease are potentially life-threatening and may lead to sepsis, shock and death. If an early diagnosis is achieved and antibiotic treatment is initiated in a timely manner, the infection can be controlled in most cases. However, progression to sepsis is still associated with particularly high mortality. In industrialized countries, vaccines are available to protect individuals at risk. However, this does generally not apply to developing countries in Africa and Asia, where most cases occur. Still, according to current knowledge, splenic fever may occur in any country. Contrasting opinions exist regarding the real risks of a potential bioterrorist attack involving Bacillus anthracis.
Patient Information
Anthrax or splenic fever, as it was formerly called, is a zoonotic disease: It mainly affects animals, namely cattle, sheep, goats, and horses, and people working with infected animals or processing contaminated animal products are at risk of contracting the disease. The causative agent of the disease is called Bacillus anthracis and it is able to form highly resistant spores that may be inhaled or ingested by human beings, but that may also penetrate the skin in case of wounds:
- Those who develop pulmonary anthrax after the inhalation of spores may develop malaise, fatigue, fever, chills, dyspnea and non-productive cough, nausea and vomiting, non of which are specific for anthrax. Therefore, it is of utmost importance to inform the attending physician about exposure to possible sources of infection as indicated above.
- In case of ingestion of Bacillus anthracis, ulcers may form anywhere in the digestive tract: While they are readily visible within the oral cavity or pharynx, they may remain undetected in other parts of this organ system. Symptoms typical of gastrointestinal anthrax are fever, nausea, vomiting, diarrhea, and abdominal pain. This variant of the disease may also follow a life-threatening course, which is why an early diagnosis is as important as in inhalative anthrax.
- Finally, individuals suffering from cutaneous anthrax will develop a papule at the port of entry. In the following days, vesicles and edematous swelling may become visible. Ulceration and eschar formation occur subsequently. Cutaneous anthrax may follow a self-limiting course, but systemic dissemination cannot be ruled out either.
Combined antimicrobial treatment is recommended in case of infection with Bacillus anthracis. An early diagnosis is essential for a favorable prognosis. Complete recovery is to be expected if treatment is initiated in a timely manner.
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