Radiographic findings of thick walled cavities in the lungs are typically seen in mycobacterial infections, malignant lesions, fungal infections, pulmonary vasculitis or other inflammatory lesions of the lungs. Necrotizing infections of the lungs caused by gram negative bacteria (Klebsiella, Psudomonas, Legionella) and Staphylococcus aureus may also form cavities of varying thickness, with consolidation. Escherichia coli pneumonia causing pulmonary cavities is very rare and the few cases reported are of pneumatocele formation. Here we present an unusual case of Escherichia coli infection as a rare cause of bilateral cavitating necrotizing pneumoniae, in a 67 year old male with uncontrolled type 2 diabetes mellitus.

INTRODUCTION Community-acquired pneumonia (CAP) Is a common and serious illness despite the availability of potent new anti-microbials and effective vaccines. For patients with community-acquired pneumonia, diabetes mellitus is one of the most common underlying diseases. AIMS AND OBJECTIVES 1) To determine the aetiological agents of CAP in T2DM, 2) To determine what percentage of CAP diagnosed by British Thoracic society guidelines is actually due to M. Tuberculosis in T2DM, 3) To study the clinical profile of CAP in T2DM and 4) To determine the factors predicting mortality. MATERIALS AND METHODS 1) Cases were selected as mentioned in inclusion criteria. 2) Informed consents were obtained. 3) All patients were evaluated by a detailed history, complete physical examination, CXR, CBC, RBS, RFT, LFT, Sputum and blood cultures and Sputum AFB. 4) Data was analyzed using SPSS v20.0 Tuberculosis cases were excluded when the clinical profile of CAP was studied. RESULTS A total of 89 cases were studied. 5 cases were found to have Tuberculosis as an etiology. Microorganisms could be isolated in 19% of the rest of the cases (84). Gram negative organisms were isolated more (56%) than gram positive organisms. Most common bacteria isolated was K. pneumoniae. The mortality was 16%. Out of the factors studied presence of coexisting CKD, COPD; breathlessness, tachycardia, tachypnea, hypotension and altered sensorium at presentation, impaired renal function and thrombocytopenia were significant predictors of mortality. CONCLUSIONS Tuberculosis is an important differential to be considered in CAP like presentation. The isolation of organisms by routine sputum and blood cultures is low. Of the organisms isolated Gram Negative organisms predominates in this area. Co-existing COPD, CKD, tachycardia, tachypnea, hypotension and altered sensorium at presentation, impaired renal function and thrombocytopenia are important predictors of mortality in patients of CAP with T2DM.

BACKGROUNDType 2 diabetes is growing in epidemic proportions worldwide, particularly in Asian subcontinent and especially in India. The disease takes a toll on the health system of a country, especially the developing nations.