AUTOPSY FINDINGS IN 27 CHILDREN WITH HEMOPHAGOCYTIC LYMPHOHISTIOCYTOSIS

Aims: Primary haemophagocytic lymphohistiocytosis (HLH) is a fatal chi ldhood disorder. The diagnosis is difficult to establish, clinically a s well as histopathologically, and it is markedly underdiagnosed. Beca use of these difficulties, we wanted to elucidate the histopathologica l findings in population-based patient material. Methods and results: The post-mortem findings in 27 children with primary HLH diagnosed in Sweden between 1971 and 1986 was reviewed, Twelve of these patients ha d an affected sibling and three additional children had parental consa nguinity, Some of the children showed generalized disease, whereas in others only one or a few organs were affected, The major histological alteration was an accumulation of primarily lymphocytes, but also of h istiocytes, some of which exhibited evidence of haemophagocytosis, The haemophagocytic activity may be difficult to detect if there are pron ounced post-mortem changes, particularly in the spleen, and it: is the refore preferable to perform the autopsy as soon as possible after dea th in order to minimize autolysis, Haemophagocytosis was most commonly observed in the spleen (17/24), the lymph nodes (17/23) and the bone marrow (9/23). indicating that a negative bone marrow examination does not rule out this diagnosis. Three additional patients had discrete s igns of haemophagocytosis in the bone marrow, In the spleen, the lymph nodes and the bone marrow, lymphocytic depletion, pronounced in some cases, could be observed, even without Drier treatment with steroids o r cytostatics, In the liver, most of the patients demonstrated an infi ltration of lymphocytes into the portal tracts similar to that seen in chronic persistent hepatitis (22/27), a finding which is uncommon in infancy and therefore suggestive of the diagnosis HLH. Other organs in volved included the thymus, lungs, intestine, pancreas, kidney, heart and striated muscle. Conclusions: The diagnosis of HLH must be based o n clinical, histological and additional laboratory findings, ii negati ve bone marrow examination is common. Previous treatment with steroids and/or cytostatic drugs may attenuate or even eliminate the typical h istological findings, Liver findings similar to those in chronic persi stent hepatitis are common.