Hemophagocytic Lymphohistiocytosis: Clinical Profile and Outcome in Libyan Children

Abstract

Background and aims: Hemophagocytic lymphohistiocytosis (HLH) is an uncommon illness of pathogenic immune dysregulation that can emerge as a familial disorder or as a random condition in response to various causes. The aim of the study was to describe the clinical profile and outcome of children with HLH followed at Tripoli Children Hospital (TCH). Methods. Medical records of patients diagnosed with HLH according to the revised HLH-2004 guidelines were reviewed for the last ten years. Symptoms at presentation, test results, etiology, HLH progression, and outcome were recorded and investigated. Results. In the last ten years, HLH has been identified in 22 patients. Six male patients (27%) and sixteen female patients (73%) were present. The age range was 1.5 to 96 months, and the male: female ratio was 1:3.8. Out of the eight HLH-2004 criteria, all patients had met five to six criteria. All the patients had a fever, with a mean temperature of 38.8 C ± 0.63. Diarrhea was found in twelve children (about 55%). Eight patients (36%) had chest symptoms, seven patients (32%) had neurological symptoms, six patients (27%) had lymphadenopathy, and twenty-two patients (100%) had hepato-splenomegaly. Eleven patients (50%) had ascites, and nine (41%) had a rash. Both viral infection and vaccination have been associated with HLH in six cases (27% each). All the cases were anemic and had thrombocytopenia; 41% had leucopenia, and 25% had leukocytosis. 83% of the patients had hypertri-glyceridemia, and 50% had positive D-dimer tests. Familial HLH (FHLH) occurred in thirteen patients (59%) and five patients (23%) with primary immune deficiency diseases, and four patients (18%) with secondary HLH in association with infection and cancer. HLH family history was present in thirteen cases (59%), and consanguineous parents were present in about 45% of the patients. The overall survival percentage was (36%); two patients (9%) resolved, five patients (23%) were transplanted, one patient (4%) was still on treatment, and fourteen patients (64%) died with no hematopoietic stem cell transplant (HSCT) following remissions and relapses. Conclusion. HLH is a relatively uncommon disease in children. With high physician and family awareness, early diagnosis can result in a better prognosis. When no HSCT facility is available, especially for the primary type, the disease can be controlled but not cured.