Description of TEMPI syndrome in Waldenström's macroglobulinemia

TEMPI syndrome (telangiectasia, erythrocytosis with increased erythropoietin, monoclonal gammopathy, perinephritic fluid collections, and intrapulmonary shunts) was described by David Sykes in 2011. By the end of March 2025, we have found descriptions of 35 cases of TEMPI syndrome in the literature. Non-IgM monoclonal gammopathy of clinical significance was diagnosed in 23 patients, multiple myeloma in 10 patients and Waldenström's macroglobulinemia in only 2 cases. Sykes estimated the median interval from the first symptoms to the diagnosis at 10 years. For many years, these patients were treated for a misdiagnosis of secondary erythrocytosis or primary polycythemia.

In 2015, an increase in hemoglobin and hematocrit concentrations was found in the patient. The diagnosis was concluded as secondary erythrocytosis in obstructive bronchopulmonary disease. Telangiectasias, which appeared soon after the detection of erythrocytosis, were misinterpreted as a manifestation of hepatopathy. The patient was treated with therapeutic phlebotomy. In 2024, symptoms of pleural effusion, ascites, swelling of the perineum and genitals appeared. This was the reason for admission to the hospital.

CT scan in 2024 revealed pleural effusions, large perinephritic fluid collections and confirmed clinically evident swelling of the perineum and genitals (pelvic effusion). This gave rise to the suspicion of TEMPI syndrome. The results of morphological, flow-cytometric and molecular biological examination of the bone marrow and high concentrations of total immunoglobulin type IgM (40.6 g/L) and monoclonal immunoglobulin type IgM (23.6 g/L) with cryoglobulin properties corresponded to Waldenström's macroglobulinemia. Contrast echocardiography confirmed the existence of arteriovenous shunts, which could not be localized by other methods. Other abnormalities included very low levels of vitamin B12 and folic acid. Laboratory examination did not show significant endocrinopathy. After therapeutic plasmapheresis, treatment with rituximab, bendamustine and dexamethasone was started in December 2024.

In each differential diagnosis of secondary erythrocytosis, it is necessary to examine monoclonal immunoglobulin to exclude its cause in TEMPI or POEMS syndrome. A large perinephritic fluid collection is diagnostic of only two diagnoses, TEMPI syndrome or renal lymphangiomatosis, while other renal diseases can cause a smaller volume of perirenal fluid collection.