An unusual cause of multiple organ dysfunction syndrome in the pediatric intensive care unit: hemophagocytic lymphohistiocytosis.

OBJECTIVE: To report our experience in children with primary or secondary hemophagocytic lymphohistiocytosis (HLH) presented with multiple organ dysfunction syndrome (MODS) in pediatric intensive care unit (PICU).

DESIGN: The records of patients with a diagnosis of HLH and MODS between January 2005 and January 2008 were reviewed. The patients' characteristics, treatment modalities, and outcomes were assessed.

SETTING: PICU of Ege University Hospital.

PATIENTS/SUBJECTS: Twelve children who were hospitalized in the PICU met the diagnostic criteria for HLH, and presented with MODS were entered into the study.

RESULTS: The median age of the patients was 3 years (range, 2 months-15.5 years). Six patients had a history of parental consanguinity and two had an affected sibling. Five of the patients were classified as primary HLH. All of the patients had hepatosplenomegaly, elevated ferritin levels, hypofibrinogenemia, anemia, thrombocytopenia, and hemophagocytosis in bone marrow examination at presentation. The median Pediatric Logistic Organ Dysfunction score of the patients at onset was 51 (range, 12-62). Four patients had six, four had five, two had four, and the remaining two had three organ dysfunctions. Organ dysfunction, other than hematologic dysfunction which was present in all patients, was most commonly seen in hepatic (n = 11, 91.7%), respiratory (n = 11, 91.7%), and cardiovascular systems (n = 10, 83.3%). Although nine patients showed neurologic dysfunction including convulsion and coma, renal failure was detected in five patients. Eleven patients were supported with mechanical ventilation and four patients required hemodialysis. Eight patients were treated according to the HLH 2004 treatment protocol, consisting of cyclosporine A, etoposide, and dexamethasone. The remaining four patients received only intravenous immunoglobulin and supportive treatment. Seven of the patients died.

CONCLUSION: HLH is a frequently lethal disease and with a clinical presentation similar to severe sepsis, MODS, disseminated intravascular coagulation, or septic shock, which are frequent diagnoses in the PICU. In the PICU, HLH should be considered in the case of prolonged fever, splenomegaly, cytopenia, and MODS. It is important for pediatricians and particularly pediatric intensivists to know the diagnostic criteria and possible clinical presentations of HLH so treatment is initiated promptly.