A case report on the co-presentation of pituitary abscess and POEMS-like syndrome

Rationale: POEMS syndrome is a rare paraneoplastic syndrome, manifesting with progressive distal polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin changes, which has multisystem manifestations and chronic cytokine overproduction. Pituitary abscess is also a rare life-threatening disease that could lead to panhypopituitarism. We report a case of pituitary abscess with high suspicion of POEMS syndrome, which to our knowledge has not been reported previously. Patient concerns: The co-presentation of pituitary abscess and POEMS-like syndrome is rare and its clinical manifestations are complex, making it easy to miss diagnosis and misdiagnosis. Long-term disease management and follow-up is crucial under this condition. Diagnosis: The patient was admitted to outside hospital due to headache, impaired consciousness, and fever since April 2024. Initial test results suggested neuroinfection. Endocrine abnormalities revealed diabetes insipidus and panhypopituitarism, including central hypocortisolism, hypogonadism, and hyperprolactinemia. Pituitary-enhanced MRI revealed abnormal pituitary signals on T1- and T2-weighted images, with peripheral rim enhancement noted after gadolinium injection. Further examination revealed lymphadenopathy, polyneuropathy, skin changes, monoclonal gammopathy (lamda chain, M-protein), ascites, meeting the diagnostic criteria for POEMS syndrome. Bone marrow core biopsy showed no malignancy. Despite the normal VEGF level, the patient was diagnosed with pituitary abscess and possibly POEMS syndrome due to other clinical presentations. Interventions: The patient underwent transsphenoidal resection of the pituitary gland lesions, antibiotic treatment and hormone replacement therapy with hydrocortisone and desmopressin. Outcomes: At 9 months of follow-up, the patient experienced recurrent fever, headache, and diabetes insipidus after discontinuation of hormone therapy. Lessons: The diagnosis of complex comorbidities is based on the combination of clinical manifestations and laboratory tests, multidisciplinary and comprehensive assessment are of great significance for this disease.