Final answer:
The diagnostic triad for HUS includes acute renal failure, microangiopathic hemolytic anaemia, and thrombocytopenia. Diagnosis follows the observation of symptoms and is confirmed with lab tests for hemolytic anaemia and renal impairment, as well as testing for Shiga toxin-producing bacteria.
Step-by-step explanation:
Diagnostic Triad for Hemolytic Uremic Syndrome (HUS)
The diagnostic triad for Hemolytic Uremic Syndrome (HUS) consists of three primary features:
- Acute renal failure
- Microangiopathic hemolytic anaemia
- Thrombocytopenia (low platelet count)
HUS most frequently occurs following an infection in the digestive system by Shiga toxin-producing Escherichia coli (STEC), which includes EHEC, or Shigella dysenteriae. The condition can lead to very severe crises that cause acute renal failure, characterized by the sudden loss of kidney function. HUS is particularly known to affect children.
Diagnosis of HUS often begins with observing symptoms such as watery diarrhea which may progress to dysentery, abdominal cramps, and in severe cases, neurological symptoms due to toxin effects on the central nervous system. Diagnostics also include laboratory findings of hemolytic anaemia, such as a decrease in haemoglobin levels, an increase in the number of fragmented red blood cells (schistocytes), and elevated bilirubin. A reduced platelet count is indicative of thrombocytopenia. Confirmation of HUS may include serological typing or PCR testing for Shiga toxin-producing bacteria and checking for renal function impairment.
It is important to note that treatment of HUS primarily involves supportive care, as antibiotic therapy can potentially exacerbate the condition by causing more toxins to be released as the bacteria die.