Isoporiasis

Infectious diseases

Clinicals - History

Fact Explanation
Diarrhea Isosporiasis is usually mild diarrheal disease caused by the coccidia Isospora belli. The parasite can be spread by ingesting contaminated food or water.
Ingested mature oocysts liberate sporozoites which invade the enterocytes of the proximal small intestine. Later they are thought to release various toxins. It causes mild diarrhea in immunocompetent individuals. The diarrhea is mild watery/ mucous type and self limiting. It may smell offensively. In the immunocompromised individuals, this diarrhea usually gets more severe. It becomes more profuse, but still watery in nature. Isosporiasis can range in severity from a chronic intermittent illness to a severe life-threatening diarrheal illness in patients with AIDS
Diarrhea
Isosporiasis is usually mild diarrheal disease caused by the coccidia Isospora belli. The parasite can be spread by ingesting contaminated food or water.
Ingested mature oocysts liberate sporozoites which invade the enterocytes of the proximal small intestine. Later they are thought to release various toxins. It causes mild diarrhea in immunocompetent individuals. The diarrhea is mild watery/ mucous type and self limiting. It may smell offensively. In the immunocompromised individuals, this diarrhea usually gets more severe. It becomes more profuse, but still watery in nature. Isosporiasis can range in severity from a chronic intermittent illness to a severe life-threatening diarrheal illness in patients with AIDS
Abdominal pain Patients may complain of crampy abdominal pain, which can last for weeks. This may accompany vomiting, malaise, anorexia and weight loss. Abdominal pain
Patients may complain of crampy abdominal pain, which can last for weeks. This may accompany vomiting, malaise, anorexia and weight loss.
Nonspecific symptoms Rarely diarrhea man abdominal pain may accompany with nonspecific symptoms such as insidiouds onset low grade fever, myalgias and headache. Nonspecific symptoms
Rarely diarrhea man abdominal pain may accompany with nonspecific symptoms such as insidiouds onset low grade fever, myalgias and headache.
At risk population Isosporiasis is most common in tropical and subtropical areas of the world such as in latin America, tropical Africa, Middle East and South East Asia. The disease is more common and severe in the presence of immunocompromized conditions such patients with AIDS or malignancy, or in patients undergoing chemotherapy. At risk population
Isosporiasis is most common in tropical and subtropical areas of the world such as in latin America, tropical Africa, Middle East and South East Asia. The disease is more common and severe in the presence of immunocompromized conditions such patients with AIDS or malignancy, or in patients undergoing chemotherapy.

Clinicals - Examination

Fact Explanation
Fever Mild fever is rare and nonspecific sign of isosporiasis. It is more pronounced among immunocompromised individuals. Fever
Mild fever is rare and nonspecific sign of isosporiasis. It is more pronounced among immunocompromised individuals.
Dehydration Signs of dehydration such as sunken eyes, extreme thirst, extreme fussiness or sleepiness in infants and children, irritability and confusion in adults, very dry mouth, skin and mucous membranes and little or no urination are also uncommon except those are immunocompromised. Dehydration
Signs of dehydration such as sunken eyes, extreme thirst, extreme fussiness or sleepiness in infants and children, irritability and confusion in adults, very dry mouth, skin and mucous membranes and little or no urination are also uncommon except those are immunocompromised.

Investigations - Diagnosis

Fact Explanation
Full blood count Parasitic infestation is characterized by high degree of eosinophilia in half of the patients. Leukocytosis and anemia (rarely) may also occur. Full blood count
Parasitic infestation is characterized by high degree of eosinophilia in half of the patients. Leukocytosis and anemia (rarely) may also occur.
Stool examination Examination of stool smears (wet smears) for oocysts
is the diagnostic investigation.
Because the oocysts may be passed in small amounts and intermittently, repeated stool examinations and concentration procedures are recommended. The oocyte is elongated in shape. Average size is 25-33 x 12-16µm. Each has a thin translucent wall with two round sporocysts, each of which has four crescentic sporozoites. If stool examinations are negative, examination of duodenal specimens by biopsy or string test (Enterotest) may be needed.
Stool examination
Examination of stool smears (wet smears) for oocysts
is the diagnostic investigation.
Because the oocysts may be passed in small amounts and intermittently, repeated stool examinations and concentration procedures are recommended. The oocyte is elongated in shape. Average size is 25-33 x 12-16µm. Each has a thin translucent wall with two round sporocysts, each of which has four crescentic sporozoites. If stool examinations are negative, examination of duodenal specimens by biopsy or string test (Enterotest) may be needed.

Management - Supportive

Fact Explanation
Fluid replacement Fluid replacement and therapy for dehydration may be the most urgently required. correction of electrolyte imbalance is also helpful Fluid losses may range from 2-20 Liters per day. Patients with severe diarrhea may require hospitalization. Fluid replacement
Fluid replacement and therapy for dehydration may be the most urgently required. correction of electrolyte imbalance is also helpful Fluid losses may range from 2-20 Liters per day. Patients with severe diarrhea may require hospitalization.
Prevention Practicing hygienic measures and avoidance of possible exposure to contaminated food and water are the effective methods of prevention. Prevention
Practicing hygienic measures and avoidance of possible exposure to contaminated food and water are the effective methods of prevention.

Management - Specific

Fact Explanation
Trimethoprim-sulfamethoxazole (Co-trimoxazole) The condition does not respond well to most of the antibiotics used to treat diarrhea. Trimethoprim-sulfamethoxazole is the usual treatment choice.
Patients with AIDS may require long-term maintenance therapy for suppression of the infection.
Trimethoprim-sulfamethoxazole (Co-trimoxazole)
The condition does not respond well to most of the antibiotics used to treat diarrhea. Trimethoprim-sulfamethoxazole is the usual treatment choice.
Patients with AIDS may require long-term maintenance therapy for suppression of the infection.

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