Introduction: Petersdorf and Beeson defined pyrexia of unknown origin (PUO) as a complaint with temperature surpassing 38.3⁰ C, developing over a period of at least three weeks, with no possible opinion reached after one week of inpatient investigation. In present study an attempt has been made to find out the causes of PUO based on bone marrow morphology.

Method & Materials: All the patients presenting with classical PUO coming to Government Medical College, Jammu, fulfilling the criteria of Petersdorf RG et al whether inpatient or outpatient over a period of two years were included in this prospective study.

Results: Out of 76 patients 48 were males and 28 were females. Age of patients varied from 12 years to 70 years. Majority of patients were in the age group of 30-44 years comprising of 45% of total cases.Anemia was seen in nearly 50% of cases of PUO. Most common diagnosis was neoplastic changes, seen in 20% of patients, 16% cases show megaloblastic changes, iron deficiency was seen 10 % cases, reactive myeloid hyperplasia seen in 18% cases, hemophagocytosis in 6% cases, 5% cases show hypocellular marrow. Among infections malaria was the commonest constituting 5.2% cases, Out of total 15 cases of neoplastic changes in bone marrow majority of them were acute myeloid leukemia seen in 40% cases.

Conclusion: Bone marrow examination is an important investigation of PUO in arriving at an etiological diagnosis.

Keywords: Pyrexia of unknown origin, Bone marrow examination, Malignancy, Hematological.

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Dr Ritu Bhagat

Department of Pathology, Government Medical College, Jammu, J&K, India