Role of Bone Marrow Examination in Cases of Pyrexia of Unknown Origin

Abstract

BACKGROUND PUO refers to cases having prolonged fever the cause of which cannot be ascertained despite all diagnostic investigations. Pyrexia of unknown origin was best defined by Petersdorf and Beeson in 1961 after a study as "a temperature of 38.3 0 C (101 0 F) or greater on several occasions for more than 3 weeks duration and failure to reach a diagnosis despite 1 week of inpatient investigations". The diagnostic spectrum of PUO is changing over time and PUO remains a diagnostic challenge. Bone marrow examination plays an important role in early diagnosis of underlying cause for pyrexia of unknown origin and can influence the management of patients. MATERIALS AND METHODS It is a one-year prospective study. A total of 360 aspirations were done, of which 82 aspirations were performed for PUO as a part of diagnostic work up. RESULTS Bone marrow examination of 82 patients presenting as pyrexia of unknown origin was performed. Of a total of 82 cases, 52 cases (63.4%) were males and 30 cases (36.5%) were females. In children, 7 cases (3.7%) had acute lymphoblastic leukaemia followed by 4 cases (14.8%), showing haemophagocytosis while 3 cases showed megaloblastic changes (11.1%). 4 cases showed reactive changes only. In adults, neoplasm was seen in majority of cases 13 cases (23.6%), followed by megaloblastic anaemia in 12 cases (22%) 9 cases were reported as reactive changes followed in frequency by iron deficiency anaemia 5 cases, while mixed deficiency was seen in 2 cases. Atypical marrow infiltration, aplastic marrow and infectious aetiology (falciparum and leishmaniasis) were also seen in few cases. CONCLUSION Bone marrow examination is an adjuvant part of investigation of PUO in arriving at an aetiological diagnosis and subsequent treatment. The most frequent causes of pyrexia of unknown origin observed in children were acute lymphoblastic leukaemia, haemophagocytosis, whereas in adults, the main causes were malignancies, megaloblastic anaemia, iron deficiencies anaemia and infection.