Clinicopathological profile of salmonella typhi and paratyphi infections presenting as Fever of unknown origin in a tropical country.
BACKGROUND
Enteric fever, a common infection in the tropics and endemic to India, often manifests as an acute febrile illness. However, presentation as fever of unknown origin (FUO) is not uncommon in tropical countries.


METHODS
We aim to describe the clinical, laboratory and pathological features of patients hospitalized with fever of unknown origin and diagnosed as enteric fever. All culture proven cases of enteric fever were analyzed retrospectively over a period of three years from January 2011 to December 2013.


RESULTS
Seven of 88 (8%) cases with enteric fever presented as FUO. Abdominal pain was the most common symptom besides fever. Relative bradycardia and splenomegaly were uncommon. Thrombocytopenia was the most common haematological abnormality while leucopenia was rare. Transaminase elevation was almost universal. S. Typhi and S. Paratyphi A were isolated from six cases and one case respectively. Yield of organisms from blood culture was superior to that of bone marrow aspirate. Multiple granulomas were identified in 4 out of 6 (67%) of the bone marrows studied, including that due to S. Paratyphi A and histiocytic hemophagocytosis was noted in two cases.


CONCLUSIONS
FUO is a relatively common manifestation of enteric fever in the tropics. Clinical and laboratory features may be atypical in such cases, including absence of relative bradycardia, leucopenia, and presence of thrombocytopenia, bicytopenia or pancytopenia. In addition, in endemic countries, enteric fever should be considered as a differential diagnosis, next to tuberculosis, in the evaluation of bone marrow granulomas in cases with FUO and culture correlation should be mandatory.
Pondicherry Institute of Medical Sciences, Ganapathichettikulam, Pondicherry, India.
Nayyar
N
Iqbal
Pondicherry Institute of Medical Sciences, Ganapathichettikulam, Pondicherry, India.
Aneesh
A
Basheer
Pondicherry Institute of Medical Sciences, Ganapathichettikulam, Pondicherry, India.
Sudhagar
S
Mookkappan
Pondicherry Institute of Medical Sciences, Ganapathichettikulam, Pondicherry, India.
Anita
A
Ramdas
Pondicherry Institute of Medical Sciences, Ganapathichettikulam, Pondicherry, India.
Renu G'Boy
RG
Varghese
Pondicherry Institute of Medical Sciences, Ganapathichettikulam, Pondicherry, India.
Somanath
S
Padhi
Pondicherry Institute of Medical Sciences, Ganapathichettikulam, Pondicherry, India.
Bhairappa
B
Shrimanth
Pondicherry Institute of Medical Sciences, Ganapathichettikulam, Pondicherry, India.
Saranya
S
Chidambaram
Pondicherry Institute of Medical Sciences, Ganapathichettikulam, Pondicherry, India.
S
S
Anandhalakshmi
Pondicherry Institute of Medical Sciences, Ganapathichettikulam, Pondicherry, India.
Reba
R
Kanungo