Pneumococcal HUS in infancy masking DGKE-related thrombotic microangiopathy with secondary hemophagocytic lymphohistiocytosis.
Derya Cevizli, Emre Leventoğlu, Özlem Gül Kırkaş et al.
✦ AI-curated · Sources linked
Case in brief
A 7-month-old boy presented with pneumonia, anemia, thrombocytopenia, and acute kidney injury. Pneumonia on imaging, elevated CRP, and a positive nasopharyngeal pneumococcal PCR initially supported pneumococcal-associated HUS. However, microangiopathic hemolysis and anuria continued despite infection control, dialysis, plasma exchange, and complement inhibition. Genetic testing identified a homozygous DGKE mutation, establishing complement-independent thrombotic microangiopathy. His subsequent course was complicated by secondary hemophagocytic lymphohistiocytosis associated with severe inflammation and catheter-related sepsis.
What made this case unusual
An apparent pneumococcal trigger initially obscured DGKE-related TMA; persistent disease activity was also complicated by secondary HLH.
Diagnostic / clinical pearl
In an infant with TMA, an infectious trigger does not rule out an underlying genetic cause. Persistent hemolysis or anuria despite infection control should prompt consideration of genetic evaluation.
Why it matters
The case also highlights HLH as a possible hyperinflammatory complication during persistent TMA, particularly in the setting of severe inflammation and catheter-related sepsis.