Discussion
We presented a young female patient who had HLH secondary to AOSD. His clinical and laboratory findings included fever, arthralgia, salmon-colored rash, lymphadenopathy, negative ANA, negative rheumatoid factor. She had hemophagocytosis. So she had five out of the eight diagnostic criteria of HLH. Then, the patient was diagnosed with HLH followed by AOSD (6, 7).
Still’s disease is an autoimmune disorder. Still’s disease with adult onset (AOSD) has two ranges of presentation including 15-25 and 36-46 years of age (8). The etiology of this disease is not clear. Some factors including infections genetic factors, (viral or bacterial), and immune disorders are suggested (8).
AOSD is characterized by fever, non-suppurative pharyngitis, transient rash (salmon-colored, maculopapular, nonpruritic, and often observed during febrile episodes) involving the trunk and proximal extremities, arthralgia that commonly involving the wrists, ankles, knees, and elbows (8). Our case had fever, pharyngitis, rashes with trunk involvement, and arthralgia especially in phalanxes.
Laboratory findings in AOSD are similar to other autoimmune disorders. Common laboratory findings are elevated white blood cell (WBC) count, abnormal LFTs, and elevated levels of CRP, and ferritin. In this disease, RF and ANA are usually negative. For diagnosis of AOSD, physicians should exclude infections disorders, vasculitis, malignancies, and other connective tissue disorders (8). We were suspicious to AOSD but we also excluded malignancies and infections disorders by different evaluations of the patient.
Of the most serious complications of AOSD is HLH. AOSD and HLH have similar clinical findings and laboratory results. These similar features make a diagnostic challenge for physicians (9). HLH unlike to AOSD may have thrombocytopenia or leukopenia, and very high levels of triglyceride in serum (10). We observed significant elevation in LFT, LDH, Ferritin, CRP, WBC levels. Thrombocytopenia and anemia (low level of hemoglobin) were observed in the laboratory tests of our case. Laboratory and clinical findings accompanying with decreasing trends of lineage blood cells suspected us to diagnose AOSD + HLH in the patient.
We found high levels of serum ferritin in our case. It seems that a key to diagnosis AOSD is very high serum ferritin. Such a finding occurs in AOSD with HLH (11).
The treatment of HLH are corticosteroids and cyclosporine. Non- steroid anti inflammation drugs and corticosteroids were recommended for treatment of AOSD. We used a combination of these treatments for our patient and she responded to these treatments and was discharged with a good condition.