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Neurology India, Vol. 53, No. 3, July-September, 2005, pp. 364-365 Letter To Editor Granulomatous hypophysitis Bhardwaj Minakshi, Sharma Alok, Pal HillolK Departments of Pathology and Neurosurgery, Dr. Ram Manohar Lohia Hospital, New Delhi Date of Acceptance: 20-Feb-2005 Code Number: ni05130 Sir, Inflammatory pituitary lesions are extremely rare with an estimated annual incidence of one case in ten million population.[1] Histologically these can be lymphocytic, granulomatous, xanthomatous, and necrotizing hypophysitis. Granulomatous hypophysitis is a chronic inflammatory condition of the pituitary, first described by Siμnds in 1917.[2] Majority of pituitary granulomas represent a specific lesion such as syphilis, tuberculosis, sarcoidosis, or histiocytosis-X. In absence of any demonstrable causative agent, the process is termed idiopathic granulomatous hypophysitis. Isolated involvement of the pituitary by tuberculosis (pituitary tuberculoma) is very rare. Coleman and Meredith first described it in 1940, and since only then, few case reports of this entity have been recorded. [3],[4],[5] A 42-year-old woman presented with diplopia to lateral gaze on left side and left-frontal headache of 6-month duration. Her visual acuity was 6/6. A left-temporal hemianopia and left-sixth nerve peresis were found on neurological examination. Endocrinological profile revealed mild hyperprolactinemia (300 IU/l). Magnetic resonance imaging (MRI) showed a sellar mass suggestive of a pituitary adenoma [Figure - 1]. The tumor was explored via a trans-sphenoidal approach and had a yellowish gray appearance and leathery consistency. It was noncurettable, nonsuckable, and relatively avascular. Postoperatively the vision returned to normal with restoration of left-lateral rectus muscle function and normalization of left-temporal hemianopia. Hematoxylin and eosin (H&E) stained sections from the biopsy revealed focal replacement of pituitary architecture by a lymphocytic infiltrate, noncaseating eptheloid cell granulomas with giant cells and areas of fibrosis [Figure - 2] and [Figure - 3]. Staining for Acid Fast Bacilli, spirochetes, and fungi was negative. There was no evidence of extrahypophyseal systemic disease. A provisional diagnosis idiopathic granulomatous hypophysitis was thus offered. However, 3 months later, the patient complained of recurrence of headaches and intermittent diplopia to lateral gaze. The steroid dose was increased with no significant improvement. Eight months later, she noticed drooping of left eyelid, and examination showed a left-oculomotor palsy. At this stage, a decision to start antitubercular therapy (ATT) along with maintenance dose of steroids was taken. The treatment regimen comprised of isoniazid, rifampicin, and pyrizinamide for first 4 months and isoniazid with rifampicin for subsequent 14 months. There was remarkable improvement in 3 weeks with regression of all symptoms. MRI at 1 year showed complete resolution of the pituitary mass [Figure - 4]. Majority patients with inflammatory pituitary lesions present with mass effect causing headaches, nausea, vomiting, chiasmal compression, and many with endocrine abnormalities and many with both the features, as in the present case. The mild elevation of prolactin level is attributable to pituitary stalk compression. Radiological findings mimic those of an adenoma and include a homogenously enhancing sellar mass that may show suprasellar extension. Pituitary stalk thickening in an appropriate clinical setting is considered a strong predictor of an inflammatory pathology.[6] Sarcoidosis is an important differential diagnosis in this setting and could be suspected on basis of systemic involvement and appropriate laboratory investigations. It has been suggested that if suspected at presentation, inflammatory lesions of pituitary may be managed conservatively thus obviating the need for surgery.[6] Trans-sphenoidal surgery is however both diagnostic and therapeutic and should be performed in cases with progressive compression or those which show radiological or clinical progression during conservative management.[7] The present case highlights the importance of considering a tubercular etiology in the differential diagnosis of sellar lesions in this part of the world and the efficacy of ATT in their management. References
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