Difficulties in diagnosing and treating recurrent aHUS in a modern hospital setting

Background. Atypical hemolytic uremic syndrome (aHUS) is a chronic systemic disease of genetic origin, which is based on uncontrolled activation of the alternative complement pathway, leading to generalized thrombus formation in the microvasculature (complement-mediated thrombotic microangiopathy - TMA). A typical triad of aHUS symptoms includes consumptive thrombocytopenia, nonimmune hemolytic anemia, and acute kidney injury. The predominant damage to the kidneys is probably associated with the increased sensitivity of the fenestrated glomerular endothelium to such damage. At the moment, the diagnosis of aHUS is one of the diagnoses of exceptions and does not have specific pathognomonic signs. It is established on the basis of the clinical picture of the disease after excluding other forms of TMA, both primary and secondary.

Objective. Demonstration of the difficulties of diagnosing and treating aHUS using a clinical example.

Description of the clinical case. In patient I., 27 years old, since 2016, proteinuria up to 1 g/day with “empty” urinary sediment and episodes of increased blood pressure were recorded, which was interpreted as chronic glomerulonephritis. Symptoms characteristic of aHUS: anemia, decreased platelet levels, and acute kidney injury of the graft developed in the patient in the early postoperative period. However, nonspecific symptoms were regarded as consequences of significant blood loss during surgery and delayed graft function. Discussion of the diagnosis of TMA became possible primarily due to the results of a morphological study of the graft tissue and was difficult due to the development of postoperative complications and the current septic condition.

Conclusion. It is extremely important for doctors to be aware of the disease and the possibilities of its diagnosis, because a timely confirmed diagnosis of aHUS and the initiation of targeted therapy can significantly improve or completely restore the function of the affected organs.