Hemorrhagic shock and encephalopathy syndrome with hemophagocytic lymphohistiocytosis pathology caused by cytomegalovirus infection

Background

Hemorrhagic shock and encephalopathy syndrome (HSES) is a severe, rare condition with poor prognosis primarily affecting infants and young children. Symptoms include fever, shock, encephalopathy, watery diarrhea, bleeding tendency, and hepatic and renal dysfunction; however, the etiology of HSES remains unknown. We present the case of an infant who developed HSES after initial cytomegalovirus (CMV) infection, suggesting the pathogenesis of hemophagocytic lymphohistiocytosis (HLH).

Case presentation

A 56-day-old male infant was admitted to the intensive care unit due to circulatory failure and convulsive seizures. Suspecting septic shock, the infant was initially treated with catecholamines, continuous midazolam for sedation, and antibiotics. Although the seizures had temporarily ceased after admission, the patient experienced recurrent convulsive seizures on day 2 and was administered multiple antiepileptic drugs. Despite these treatments, the patient developed refractory status epilepticus, necessitating thiamylal anesthetic therapy. The initial blood, urine, and cerebrospinal fluid cultures were negative. The patient met the criteria for HSES (encephalopathy, shock, disseminated intravascular coagulopathy, watery diarrhea, cytopenia, acidemia, hepatic and renal dysfunction, and negative blood and cerebrospinal fluid cultures). Furthermore, the patient fulfilled the criteria for HLH (fever, cytopenia, hypertriglyceridemia, hypofibrinogenemia, and elevated ferritin and soluble interleukin-2 receptor levels), with prior CMV infection implicated as a potential trigger.

Conclusion

We encountered an infant who developed HSES with HLH secondary to a CMV infection. This study provides new insights into the pathogenesis of HSES involving the HLH pathology.