Aim: To determine the aetiology of Addisons disease in patients admitted to a tertiary care hospital in South India from 2001 to 2007.
Method: Forty-five patients with Addisons disease were admitted during this period. Etiological work up was carried out in all these patients.
Results: Thirteen patients (29%) had a possible infectious cause: 11.1% histoplasmosis, 8.8% confirmed tuberculosis, 4.4% presumed tuberculosis, 4.4% had unclassified granulomas. Four patients (9%) had other definable causes: lymphoma, infarction and adrenoleukodystrophy. 62% of patients in whom no cause was identified were labelled autoimmune/idiopathic.
Patients with infectious versus idiopathic Addisons disease were more often men 92% vs 48% (P=0.01), the average age these patients was 46 vs 33 years (P<0.01), these patients had higher creatinine level at presentation (median 1.5 vs 1.0 P<0.01). Presence of fever, leukocytosis or raised ESR did not discriminate patients with infectious and idiopathic Addisons disease.
These patients were followed up from 0 to 58 months. 6 of the 7 patients who underwent repeat imaging showed no change in size of the adrenal lesions.
Five patients with histoplasmosis received anti -fungal medication for 45 years. One patient who was rebiopsied after receiving 45 months of treatment had persisting histoplasma.
Summary: 30% of patients with Addisons disease are likely to have an underlying infection. These lesions can persist for many years despite treatment. In patients with histoplasmosis repeat biopsy is indicated before stopping treatment.