[Ferritin and soluble interleukin-2-receptor in the diagnosis of fever of unknown origin].

UNLABELLED: HISTORY UND CLINICAL FINDINGS: Within a few weeks, two patients aged 16 and 75 years with fever of unknown origin were referred to the emergency unit.

INVESTIGATIONS: Laboratory tests revealed increased aminotransferase levels, progressive cytopenia and an increase of inflammatory markers. In the older patient a rapid clinical detoriation with multi organ failure was observed. Progressively increasing levels of ferritin and soluble-interleukin-2-receptor levels led to the diagnosis of hemophagocytic lymphohistiocytosis, which was confirmed by bone marrow examination in the case of the younger patient.

TREATMENT AND COURSE: Immunsuppressive treatment induced a clear improvement of clinical and laboratory findings and in the case of the older patient finally led to convalescence.

CONCLUSION

Hemophagocytic lymphohistiocytosis is a rare but potentially fatal differential diagnosis, which should be considered in patients with fever and cytopenia.