Tuberculosis-associated hemophagocytic lymphohistiocytosis with initial presentation of fever of unknown origin in a general hospital

The study aimed to investigate the clinical features and prognoses of patients with tuberculosis (TB) who had secondary hemophagocytic lymphohistiocytosis (HLH).Patients first presenting with fever of unknown origin, who were ultimately diagnosed with TB-associated secondary HLH, were assessed retrospectively. We summarized and analyzed clinical manifestations, laboratory examinations, diagnoses, treatments, and prognoses of patients using clinical data, outpatient follow-up, and telephone follow-up in combination with literature review.Among patients admitted to the hospital with fever of unknown origin in the past 10 years, 371 patients were diagnosed with TB. Among them, 8 cases were diagnosed as tuberculosis-associated HLH (TB-HLH). The proportion of females among TB-HLH patients was higher than the proportion of females among TB patients. Within the same time period, 227 cases met the diagnostic criteria for HLH, among which TB-HLH patients accounted for 3.52% of the cases. None of the 8 TB-HLH patients had underlying diseases, and a majority of them had short symptom durations, rapid progression, along with multisystem and multiorgan dysfunctions. Their clinical manifestations were inconsistent with the typical clinical manifestations and imaging results characteristic of TB. Compared with patients with TB in our hospital during the same period, the 8 TB-HLH patients had a higher proportion of blood-disseminated TB and tuberculous meningitis. Apart from this, the hematological damage in these patients was higher than the common clinical manifestations of TB, and they also had a high proportion of respiratory failure. All 8 TB-HLH patients received antitubercular therapy, and 6 of them were also treated for HLH. However, their morbidity and mortality were significantly higher than that for reported cases of TB-HLH cases, both domestically and abroad, which may be attributed to the fever of unknown origin.Patients with TB-HLH had poor prognoses and no specific clinical manifestations. Therefore, cases of atypical TB and severe TB should be carefully monitored to achieve early diagnosis and early intervention.