Acute radiation sickness (ARS) or acute radiation syndrome negatively influences all organ systems, especially that of the hematopoietic system. The reason for it is the dependence on stem cells that are primarily affected in a situation of acute radiation exposure. Ionizing radiation causes damage to double-stranded DNA molecules resulting in the loss of proliferative function and damage to affected cells [1].

Acute radiation sickness expresses itself in three phases: prodromal, latent and manifestation phase.

The prodromal phase includes symptoms of the gastrointestinal (GI) tract such as nausea, vomiting, and diarrhea with consequent fluid, electrolyte loss, and anorexia. Non-specific symptoms like a headache, hypotension, fever, erythema are also present [2]. It is important to differentiate these symptoms from those of GI infections or other pathologies involving this system.

The latent phase is characterized by the discontinuation of symptoms seen in prodromal phase or mild exhibition of them. The duration of this phase is dependent on the dose of radiation certain subject was exposed to [2].

Manifestation phase follows after latent phase. The manifestation of ARS involves multiple organ systems, firstly that of the hematopoietic system [3].

• Hematopoietic syndrome takes place if the dose of exposure is in a range of 2-3 grays (Gy) [4]. Consequences of this syndrome are based on depletion of blood cells i.e. thrombocytopenia, leukopenia, and anemia [5].
• Cerebrovascular syndrome results from inflammation and damage to the blood vessels. The symptoms of this syndrome are cognitive impairments like disorientation, confusion, seizures and loss of balance. On examination, patients may be ataxic or have signs of papilledema. The absence of deep tendon and corneal reflexes is also noted [5].
• GI syndrome includes symptoms listed in prodromal phase in addition to abdominal cramps. Additionally, there is a serious risk of infections as a result of disturbances in mucosal barrier. Leukopenia caused by the hematopoietic syndrome too increases predisposition to infection. Destruction of mucosa can also lead to bleeding from GI tract, enhancing the presentation of anemia [5].
• In early stages, cutaneous syndrome manifests as erythema and edema. In contrast, late in the disease, signs like desquamation, ulceration, and onycholysis become evident [5] [6].

More serious complications of severe cases in ARS are accountable for systemic inflammatory response syndrome (SIRS) with following multi-organ failure (MOF) [1].

• Fever

  Symptoms Mild (1-2 Gy) Moderate (2-4 Gy) Severe (4-6 Gy) Very Severe (6 Gy) Lethal (> 8 Gy) Phase Symptoms Time to Onset > 30 days 18-28 days 8-18 days < 7 days < 3 days Clinical Manifestations Fatigue Fever High Fever High Fever High Fever Weakness Weakness [large.stanford.edu]

  The bone marrow syndrome is characterized by anorexia (lack of appetite), fever, and malaise. There is a drop in all blood cell counts for several weeks. The primary cause of death is infection and hemorrhage. [medicinenet.com]

  Radiation sickness with systemic symptoms can exhibit four stages in milder cases or cause immediate convulsions, high blood pressure, shock, fever, skin reddening, and death. [britannica.com]

  Some symptoms that are common with radiation sickness include nausea and vomiting, headache, fever, dizziness, disorientation, fatigue, bloody vomit and stools, hair loss, low blood pressure, and poor wound healing. [wikihow.com]

  Non-specific symptoms like a headache, hypotension, fever, erythema are also present. It is important to differentiate these symptoms from those of GI infections or other pathologies involving this system. [symptoma.com]

• Fatigue

  Some symptoms that are common with radiation sickness include nausea and vomiting, headache, fever, dizziness, disorientation, fatigue, bloody vomit and stools, hair loss, low blood pressure, and poor wound healing. [wikihow.com]

  Onset > 30 days after prodrome Duration Depends on dose and underlying host factors Possible clinical effects Fatigue Weakness Lethality None likely from radiation alone Medical response As needed for signs/symptoms Counseling and long-term effects monitoring [remm.nlm.gov]

  Radiation Sickness Pathology Cause(s) Exposure to ionizing radiation, such as x-rays or radioactive substances Symptoms Nausea, hair loss, fatigue, blistering of skin Mortality Rate High Treatments Adrenaline, fluids, palliative care Show Information [house.wikia.com]

  […] known occurrence of solar particle events (SPE) and the inability to predict their occurrence, there is a possibility the crew will suffer from acute radiation sickness (ARS) with the highest likelihood of prodromal symptoms of nausea, vomiting, and fatigue [humanresearchroadmap.nasa.gov]

  These symptoms include loss of appetite, fatigue, fever, nausea, vomiting, diarrhea, and possibly even seizures and coma. This seriously ill stage may last from a few hours up to several months. [emergency.cdc.gov]

• Anemia

  Destruction of mucosa can also lead to bleeding from GI tract, enhancing the presentation of anemia. In early stages, cutaneous syndrome manifests as erythema and edema. [symptoma.com]

  Following a latent period of six months to one year after extremely high does of radiation, protein in the urine, kidney insufficiency, anemia and high blood pressure may develop. [rarediseases.org]

  […] characterized by the following clinical signs and symptoms: 2 Nausea, vomiting, and diarrhea Mucositis, skin erythema, and fever Lymphocytopenia within 48 hours, neutropenia, and thrombocytopenia within 20-30 days Impaired wound healing, bleeding, and anemia [upmc-cbn.org]

  It can dramatically reduce the number of red blood cells, causing anemia and and increased risk of fainting. Credit: istockphoto Radiation sickness can cause visible ulcers in or on the mouth. [cbsnews.com]

  Manifestations depend on dosage, ranging from anorexia, nausea, vomiting, and mild leukopenia, to thrombocytopenia with hemorrhage, severe leukopenia with infection, anemia, central nervous system damage, and death. radiation sickness n. [medical-dictionary.thefreedictionary.com]

• Malaise

  Acute radiation sickness is characterized by nausea, vomiting, diarrhea, anorexia, headache, malaise and rapid heartbeat (tachycardia). With mild ARS, the discomfort subsides within a few hours or days. [rarediseases.org]

  The bone marrow syndrome is characterized by anorexia (lack of appetite), fever, and malaise. There is a drop in all blood cell counts for several weeks. The primary cause of death is infection and hemorrhage. [medicinenet.com]

  […] syndrome to appear Length of the prodromal period of hematologic syndrome Length if the latent period of hematologic syndrome Declines during the latent period of hematologic syndrome although there are no other signs of illness Vomiting, diarrhea, malaise [quizlet.com]

  • Symptoms are anorexia, fever, and malaise. • Drop in all blood cell counts occurs for several weeks. • Primary cause of death is infection and hemorrhage. • Survival decreases with increasing dose. • Most deaths occur within a few months after exposure [emergency.cdc.gov]

  The hallmark signs and symptoms of ARS may include: Nausea, vomiting, and diarrhea Anorexia and malaise (general feeling of discomfort) Headache Tachycardia or rapid heartbeat Severe signs and symptoms of cardiovascular and central nervous system sickness [dovemed.com]

• Weight Loss

  Clinical Symptoms of Acute Radiation Syndrome (Open Table in a new window) Acute Radiation Syndrome Clinical Symptoms >0.7 Gy Hematopoietic syndrome - anemia, neutropenia >10 Gy Gastrointestinal syndrome - nausea, vomiting, dehydration, weight loss, anorexia [emedicine.medscape.com]

  Third-stage symptoms are fever, infection, vomiting, bloody diarrhea, hemorrhages, dehydration, weight loss, hair loss, and ulcers. Death usually occurs in this phase if the damage has been sufficiently severe. [britannica.com]

  skin injury, mucositis, parotitis, weight loss, or fever confirmation of initial dose estimate using chromosome aberration cytogenetic bioassay when possible. [emergency.cdc.gov]

• Nausea

  […] and vomiting, especially if nausea and vomiting are unexplained by other causes; tendency to bleed (epistaxis, gingival bleeding, ptechiae) and/or respiratory infection with neutropaenia, lymphopaenia, and thrombocytopenia, with history of nausea and [health.gov.au]

  Acute radiation sickness is characterized by nausea, vomiting, diarrhea, anorexia, headache, malaise and rapid heartbeat (tachycardia). With mild ARS, the discomfort subsides within a few hours or days. [rarediseases.org]

  Systemic reactions to radiation include a general feeling of malaise, loss of appetite or nausea and vomiting, and headache. [medical-dictionary.thefreedictionary.com]

  Initial nausea and vomiting symptoms usually manifest within 12 to 24 hours after mild radiation exposure (1 to 2 Sv or 100 to 200 rems). [news-medical.net]

  There is initially extreme nervousness; confusion; severe nausea, vomiting, and watery diarrhea; burning sensations of the skin; and loss of consciousness. [medicinenet.com]

• Vomiting

  especially if nausea and vomiting are unexplained by other causes; tendency to bleed (epistaxis, gingival bleeding, ptechiae) and/or respiratory infection with neutropaenia, lymphopaenia, and thrombocytopenia, with history of nausea and vomiting two [health.gov.au]

  Following a dose higher than 2 Sv, most people will vomit. [upmc-cbn.org]

  For example, damage to the GI is scored by evaluating the time of onset, severity, the frequency of vomiting or diarrhea. [symptoma.com]

  Nausea and vomiting is usually the first symptom to appear. Patients who report vomiting within 4 hours or less of radiation exposure are at risk of serious GI ARS and need careful evaluation, monitoring, and treatment. [calsprogram.org]

  Medications should be administered to treat symptoms like vomiting, diarrhea, pain and burns. Fluids, electrolytes and nutrition should be maintained. Psychological support should also be offered to these patients. [medindia.net]

• Diarrhea

  For example, damage to the GI is scored by evaluating the time of onset, severity, the frequency of vomiting or diarrhea. [symptoma.com]

  There is initially extreme nervousness; confusion; severe nausea, vomiting, and watery diarrhea; burning sensations of the skin; and loss of consciousness. [medicinenet.com]

  Medications should be administered to treat symptoms like vomiting, diarrhea, pain and burns. Fluids, electrolytes and nutrition should be maintained. Psychological support should also be offered to these patients. [medindia.net]

  Patients who have onset of mild diarrhea 3 to 8 hours post exposure have likely had 4 to 6 Gy of radiation. Patients who have onset of severe diarrhea < 1 hour post exposure have likely had > 8 Gy of radiation and have a poor prognosis. [calsprogram.org]

  Prodromal Phase The primary symptoms of ARS associated with the prodromal phase include vomiting, diarrhea, headaches, and fever. [large.stanford.edu]

• Loss of Appetite

  Initial symptoms of Acute Radiation Sickness occur within 1 hour to 2 days of exposure and include: Nausea Vomiting Anorexia (loss of appetite) Diarrhea If you experience any of these symptoms following exposure to radiation, it is CRITICAL that you seek [potassiumiodide.com]

  These symptoms include loss of appetite, fatigue, fever, nausea, vomiting, diarrhea, and possibly even seizures and coma. This seriously ill stage may last from a few hours up to several months. [emergency.cdc.gov]

  During the prodromal period patients might experience loss of appetite, nausea, vomiting, fatigue, and diarrhoea; after extremely high doses, additional symptoms such as fever, prostration, respiratory distress, and hyperexcitability can occur. [health.gov.au]

  Systemic reactions to radiation include a general feeling of malaise, loss of appetite or nausea and vomiting, and headache. [medical-dictionary.thefreedictionary.com]

  Other symptoms can include diarrhea, weakness, fatigue, loss of appetite, fainting, dehydration, inflammation of tissues, bleeding from the nose, mouth, gums or rectum, and anemia. [cbc.ca]

• Blood in Stool

  Possible symptoms may include: Headache Diarrhea Fever Vomiting and nausea Dizziness Ulcers of the mouth Redness and swelling of exposed areas Sloughing of the skin Open wounds on the skin Blood in stool Bleeding from the rectum, mouth, nose, and gums [syndromespedia.com]

• Blister

  However, they progress rapidly afterwards, and the blistering is similar to that suffered by extreme burn patients. [house.wikia.com]

  Credit: istockphoto Areas of skin exposed to radiation may turn blister and turn red - almost like a severe sunburn. In some cases open sores form. The skin may even slough off. Credit: istockphoto Radiation damages hair follicles. [cbsnews.com]

  It can include swelling, itching, and redness of the skin (like a bad sunburn) or may be more severe and include blisters or ulcers. The skin may heal for a short time, followed by the return of swelling, itching, and redness days or weeks later. [emergency.cdc.gov]

  You might also have skin damage, like a bad sunburn, or get blisters or sores. Radiation may also damage the cells that make hair, causing your hair to fall out. In some cases, hair loss might be permanent. [webmd.com]

  Technically referred to as acute radiodermatitis, its effects include red patches, peeling skin, and sometimes blistering. Expect it to show up within 24 hours. [gizmodo.com]

• Alopecia

  Erythema The correct order of layers of skin, from outermost to innermost: Epidermis, Dermis, Subcutaneous The skin erythema dose necessary to affect 50% of the people irradiated is termed: SED50 The SED50 is estimated to be approximately: 600 Epilation or alopecia [studystack.com]

  Moderate exposure may cause headache, nausea, vomiting, anorexia, and diarrhea; long-term exposure may result in sterility, fetal damage in pregnant women, leukemia or other forms of cancer, alopecia, and cataracts. radiation sickness The generic term [medical-dictionary.thefreedictionary.com]

• Petechiae

  Petechiae and mucosal bleeding result from thrombocytopenia, which develops within 3 to 4 wk and may persist for months. Anemia develops slowly, because preexisting RBCs have a longer life span than WBCs and platelets. [merckmanuals.com]

• Epistaxis

  […] entering an irradiation chamber when the source is unshielded); history of proximity to an unknown (usually metallic) object with a history of nausea and vomiting, especially if nausea and vomiting are unexplained by other causes; tendency to bleed (epistaxis [health.gov.au]

• Headache

  Some symptoms that are common with radiation sickness include nausea and vomiting, headache, fever, dizziness, disorientation, fatigue, bloody vomit and stools, hair loss, low blood pressure, and poor wound healing. [wikihow.com]

  Non-specific symptoms like a headache, hypotension, fever, erythema are also present. It is important to differentiate these symptoms from those of GI infections or other pathologies involving this system. [symptoma.com]

  Systemic reactions to radiation include a general feeling of malaise, loss of appetite or nausea and vomiting, and headache. [medical-dictionary.thefreedictionary.com]

  Vomiting Onset: 2 hours after exposure or later Percent of victims who vomit at this dose: ~10-50% Diarrhea None Headache Slight Level of consciousness Unaffected Body temperature Normal Medical response Outpatient observation Hospitalization generally [remm.nlm.gov]

  A radiation dose as low as 0.35 Gy could feel a bit like you have the flu—expect nausea and vomiting, headaches, fatigue, and fever. If the body is exposed to a higher dose, somewhere between 1-4 Gy, blood cells begin to die. [gizmodo.com]

• Irritability

  Radiation sickness causes major irritation of the intestinal lining, resulting in severe and sometimes bloody diarrhea. Credit: istockphoto Areas of skin exposed to radiation may turn blister and turn red - almost like a severe sunburn. [cbsnews.com]

  Early symptoms can include skin irritation, nausea, vomiting, high fever, hair loss and burns to the skin. [cbc.ca]

It is possible to assess acute radiation sickness with a proposed medical treatment protocols for radiation accident victims (METREPOL). It is convenient in distinguishing affected organ systems based on clinical presentation. The protocol calculates severity and possible damage done to the neurovascular, gastrointestinal, cutaneous and hematopoietic systems. For example, damage to the GI is scored by evaluating the time of onset, severity, the frequency of vomiting or diarrhea [7] [8]. A score of 1 is given to a patient who does not need acute medical attention and should be referred to an outpatient clinic for further follow ups. A score of 2 is given to a patient who is in high need of professional care. And a score of 3 is given to those who are likely to suffer from multiple organ failures (MOF) and have an overall low risk of survival [7] [8].

Blood tests are of paramount importance to control the dynamics of the patient as the hematopoietic system is greatly radiosensitive. To achieve proper care, repeated blood count of granulocytes, platelets, and lymphocytes are needed about every 6 hours for the first 24h and reticulocyte count every 24h [5]. Standard biochemical tests are also necessary. If there is suspicion of radionucleotide ingestion, the analyses of urine and feces will provide appropriate evidence [5].

Biodosimetry of chromosome aberrations in lymphocytes is useful in determining the possible dose of radiation, as the severity of aberrations strongly correlate to the dosage of radiation given [5]. During biodosimetry, analysis of translocations, dicentrics and chromosome consolidations are sought [9].

Physical dosimetry is convenient for providing analysis for individual dose taken but is a technique limited in availability. It is also possible to obtain high-quality radiation dosage data from an in vivo electron paramagnetic resonance (EPR) dosimetry that works by evaluating nail or teeth [10].

As part of the comprehensive treatment, strict reverse isolation and granulocyte-macrophage colony-stimulating factor (GM-CSF) therapy were applied. All the patients recovered after an appropriate treatment for 83 days. [ncbi.nlm.nih.gov]

While low doses of radiation do not merit treatment and high doses are lethal regardless of treatment, intermediate doses can be survivable if proper treatment is initiated. [upmc-cbn.org]

COOKING, MODIFICATION OF NUTRITIVE QUALITIES, PHYSICAL TREATMENT 33 Modifying nutritive qualities of foods; Dietetic products; Preparation or treatment thereof 10 using additives A23L 33/115 A HUMAN NECESSITIES 23 FOODS OR FOODSTUFFS; THEIR TREATMENT, [patentscope.wipo.int]

Table 1 stratifies the risk and prognosis from radiation exposure based on lymphocyte counts 48 hours after exposure. 2 Table 1: Lymphocyte Counts and Prognosis 48 hr. lymphocyte count Est'd radiation dose Prognosis 1000-1500 cells/mm 3 1-2 Sv Good 500 [upmc-cbn.org]

It is typically difficult to predict the prognosis in such cases Some individuals who have low dose exposure or only have a small part of their body affected, generally will have a better prognosis than those who are exposed to a high dose or have total [dovemed.com]

The quicker symptoms appear, the worse the prognosis for patients of ARS. [calsprogram.org]

The higher the dose of radiation, the sooner these symptoms appear - and the worse the prognosis. Someone who starts to vomit within one hour of exposure is likely to die. [cbsnews.com]

Significant comorbidities, injuries, and burns worsen prognosis. [merckmanuals.com]

(Etiology) Acute Radiation Syndrome is caused by the following factors: Exposure to ionizing radiation that may come from: High energy X-rays used in diagnosis and therapy Radiation inside nuclear reactors, cyclotrons, linear accelerators, alternating [dovemed.com]

The circumstances of human exposures (therapeutic, accidental, warfare) are then considered in the light of extensive epidemiological data. [books.google.com]

What is feasible and desirable in the epidemiological follow-up of Chernobyl. In: A. Karaoglou, G. Desmet, G.N. Kelly & H.G. [keynes.scuole.bo.it]

Both of these findings, however, need confirmation in well-designed epidemiological studies. The absence of demonstrated increases in cancer risk – apart from thyroid cancer – is not proof that no increase has occurred. [who.int]

A subset of the Life Span Study (the Adult Health Study) is examined clinically every two years; this clinically examined subset also forms the basis of cytogenetic, immunological, and molecular epidemiologic studies. [stat.ucla.edu]

The validity of such extrapolations cannot be confirmed because the hypothesized increase in risk is too small to be detected in epidemiologic studies, and the possibility that there is no increased cancer risk due to this exposure cannot be excluded. [merckmanuals.com]

With supportive therapy, people who have been exposed to levels as high as 5-6 Sv can survive. 1 ARS refers to a spectrum of pathophysiological effects that are induced when high doses of ionizing radiation interact with the human body. [upmc-cbn.org]

Not only did the drug prevent the destruction of the intestinal barrier cells, it boosted biomarkers characteristic of cell repair. [popsci.com]

Radiation Exposure Injuries The tables below show the symptoms that manifest with localized cutaneous radiation injury, acute radiation syndrome, and lethal doses of radiation according to the Centers for Disease Control and Prevention. [1, 2] Table 1 [emedicine.medscape.com]

Orphan designation had been granted in the United States for preventing death following a potentially lethal dose of radiation in a radiation disaster. [ema.europa.eu]

Nevertheless, the parts of the body that are not being x-rayed will be shielded with a lead apron to prevent unnecessary exposure. The technician, meanwhile, will leave the room when taking the image. [medicalnewstoday.com]

Infections should be prevented and treated with antibiotics. Medications should be administered to treat symptoms like vomiting, diarrhea, pain and burns. Fluids, electrolytes and nutrition should be maintained. [medindia.net]

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