Transplant-associated thrombotic microangiopathy and acquired nephrotic syndrome: A case report in a 35-month child.

Abstract Background Transplant-associated thrombotic microangiopathy (TA-TMA) presents with thrombocytopenia, nonimmune hemolytic anemia, peripheral blood schistocytes and end-organ damage to the kidney. TA-TMA is associated with a significant increased morbidity and mortality, especially when treatment is not initiated early. We present a pediatric clinical case of a 35-month child with history of hepatic transplantation, who develop the clinical spectrum of TA-TMA and acquired nephrotic syndrome. Case presentation: A 35-month-old boy with history of hepatic transplantation secondary of atresia of biliary ducts who received immunosuppressive therapy with tacrolimus, mycophenolate and steroids. He presents with 4 days of fever, vomiting, and non-dysenteric diarrhea. He received an initial course of antibiotics without response. After 3 days he continues with fever, low urine output and edema. Vital signs showed high blood pressure and physical exam revealed facial and extremity edema. Laboratory results showed proteinuria and hematuria, low albumin, and high triglycerides. All possible etiologies of nephrotic syndrome were ruled out. Kidney biopsy showed TMA changes. Plasma exchange and Eculizumab were started with clinical improvement. Discussion TMA can be classified as a primary or secondary. Primary TMA can be hereditary or acquired. Acquired TMA included the ones triggered by medications. This clinical syndrome has been described as an endothelial dysfunction secondary of an immune reaction over the endothelium and/or a direct cytotoxic effect over endothelium and platelets. In this case report the use of calcineurin inhibitors (tacrolimus) one of the most common drugs associated with TMA was one the triggers factors. Recent publications have described how these patients that are exposed to any triggers has also a genetically predisposing to develop TMA. There is a lack in diagnostics and prognostic markers. The earliest treatment is stared, the better prognosis and outcomes.