A 60-year-old female was referred for a left adrenal 35-mm mass detected on imaging for weight loss over one year, associated with anorexia, nausea and abdominal discomfort. Her background included hypertension and seronegative arthritis on prednisolone. Biochemical evaluation showed no adrenal hormone hypersecretion and left adrenalectomy was performed due to concern of malignancy. Subsequent histology showed necrotising granulomas and FDG-PET/CT revealed FDG-avidity in contralateral adrenal, thoracic and right cardiophrenic lymph nodes. She emigrated from Burma to Australia 30 years ago. Prednisolone was ceased and empirical rifampicin, isoniazid, pyrazinamide, ethambutol was initiated for tuberculosis. One week later, she was admitted with an adrenal crisis. Primary adrenal insufficiency was confirmed on Short Synacthen test and elevated ACTH. Adrenalectomy likely reduced reserve, then rifampicin CYP3A4-induction increased cortisol clearance. Retrospectively, she had two years of skin hyperpigmentation, thought to be lichen planus pigmentosus, then melasma. This improved following hydrocortisone replacement, and in hindsight was related to primary adrenal insufficiency. After eight months of anti-tuberculous treatment, there was resolving FDG-activity of right cardiophrenic and thoracic lymphadenopathy suggesting treatment response. Moderate activity in the right adrenal with normal appearance on CT persists.
Since Thomas Addison first described primary adrenal insufficiency from adrenal TB, its incidence has declined in developed countries.1 In patients presenting with either adrenal masses or insufficiency, it should still be considered as a differential in patients with appropriate demographic and risk factors. Diagnosing adrenal TB may not be straightforward if adrenal resection is not indicated or extra-adrenal sites not obvious or biopsy-amenable. TB in the adrenal may also not necessarily display imaging abnormality. FDG-PET/CT is sensitive in evaluating activity, extent, and treatment response in pulmonary TB, however use for monitoring treatment response in extra-pulmonary disease is unclear.2,3 There are only rare case reports of recovery of adrenal function following anti-tuberculous treatment.4