Diagnosis of Dysentery
The diagnosis of dysentery usually begins with a medical history and physical examination. Doctors ask about recent travel, hygiene practices, food and water consumption, and whether others in the household are showing similar symptoms. Since dysentery presents with bloody diarrhoea, cramping, and fever, healthcare providers aim to quickly confirm the cause and start treatment.
A stool sample is the most important diagnostic tool. Testing the stool allows doctors to identify whether the infection is caused by bacteria, parasites, or another agent. In bacillary dysentery, the stool will often test positive for Shigella bacteria. While in amoebic dysentery, Entamoeba histolytica cysts or trophozoites may be found. In some cases, further laboratory culture or antigen testing may be required.
Doctors also check for signs of dehydration. If a patient shows symptoms such as low blood pressure, dry mouth, reduced urine output. Additionally, sunken eyes may require urgent fluid replacement. In severe cases, blood tests may be done to evaluate kidney function and electrolyte levels.
In South Africa, especially in public hospitals and rural clinics, the diagnosis of dysentery is often made based on clinical presentation alone—particularly during outbreaks or when laboratory services are limited. Where stool testing is not immediately available, doctors may treat presumptively based on symptoms, travel history, and community exposure.
Imaging, such as an ultrasound or CT scan, is rarely needed but may be used in severe cases where complications like a liver abscess (from amoebic infection) are suspected. This can help distinguish between intestinal and extra-intestinal disease, particularly in patients with right-sided abdominal pain or prolonged fever.
It is important to rule out other causes of bloody diarrhoea, such as inflammatory bowel disease (e.g. ulcerative colitis or Crohn’s disease), colorectal cancer, or other parasitic infections. Misdiagnosis can delay appropriate treatment and increase the risk of complications.
Diagnosis of Dysentery
Accurate and early diagnosis of dysentery is crucial. It helps guide the correct use of antibiotics or anti-parasitic medication, ensures the patient is isolated if necessary, and reduces the risk of spreading the disease to others. In community settings such as schools or workplaces, diagnosis also triggers important public health responses.
In resource-limited settings, improving access to diagnostic tools—such as point-of-care stool tests—would significantly improve early detection and outbreak control. Until then, awareness, clinical training, and rapid response protocols remain vital in managing dysentery effectively.
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