[77-year-old female with hyponatremia, pruritus and papulous exanthema].

HISTORY AND CLINICAL FINDINGS: A 77 year old female patient was admitted for the evaluation of hyponatremia and a generalized papulous exanthema with severe pruritus.

INVESTIGATIONS AND DIAGNOSIS: The syndrome of inappropriate antidiuretic hormone secretion (SIADH) could be diagnosed as cause for hyponatremia. Biopsy of a soft tissue tumor revealed a T-cell lymphoma with widespread skelettal dissemination.

TREATMENT AND COURSE: Chemotherapy caused a rapid response and improvement of general well-being. SIADH could be controlled by the specific vasopressin-2-receptor antagonist tolvaptan.

CONCLUSIONS

In this patient, both the papulous exanthema and the SIADH are regarded as T-cell-lymphoma-associated paraneoplastic syndromes.