Background: Pyrexia of unknown origin (PUO) is a diagnostic dilemma in clinical practice. Despite the proper accessibility of different investigations, still diagnosis cannot be reached. The aim of the study was to determine the causes of PUO in a tertiary care hospital located in Northern Andhra.

Materials and Methods: This study was a prospective observational study done in the department of General Medicine in tertiary care Hospital over period of 10 months from November 2019 to august 2020. All patients who satisfied the inclusion criteria and exclusion criteria were taken into the study.

Results: out of 100 patients 65 were male and 35 were female. Infectious causes found to be the most common cause out of which Tuberculosis was most common; followed by neoplasms and then connective tissue disorders.

Conclusion: The most common cause of PUO in this study was infectious causes (Tuberculosis). Undiagnosed cases are still problematic condition that needs exhaustive investigations.

Keywords: PUO- pyrexia of unknown origin, Tuberculosis, Neoplasms, Connective tissue disorders.

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Dr P.S.R.Aneesh

Post Graduate, General Medicine, Andhra Medical College, Visakhapatnam