[Autoimmune encephalitis due to mantle cell lymphoma]. / Auto-immune encefalitis door een mantelcellymfoom.

BACKGROUND: Autoimmune encephalitis is a rare condition characterized by subacute development of cognitive and psychiatric symptoms. A paraneoplastic syndrome involves autoimmune encephalitis caused by classic antibodies. Although this condition is often associated with cancer, no malignancy has yet been found in 70-90% of patients at the time of diagnosis. CASE DESCRIPTION: We saw a 58-year-old male patient with fatigue, diarrhoea and weight loss. He was also experiencing hyperekplexia, personality changes and an instable gait. PET-CT revealed generalised lymphadenopathy. Histopathological analysis of a lymph node showed mantle cell lymphoma. Further investigation of the fluid revealed anti-DPPX IgG antibodies. We treated the patient's mantle cell lymphoma with R-CHOP; he achieved complete remission and his neurological symptoms resolved almost completely. CONCLUSION: The presence of anti-DPPX IgG antibodies is rare. Although it has not been proven that these antibodies are related to malignancies, this is the third of 30 known cases in which anti-DPPX IgG antibodies and a lymphatic malignancy were found.

(18)F-fluoride-PET for dynamic in vivo monitoring of bone formation in multiple myeloma.

BACKGROUND: Bone disease in multiple myeloma is characterized by reduced bone formation. The gold standard of bone formation is the mineral apposition rate (MAR), an invasive technique reflecting bone formation at a single site. We compared (18)F-fluoride-PET with the MAR in myeloma patients. METHODS: Bone formation was measured before and after bortezomib treatment by determination of the MAR in iliac bone marrow biopsies and the measurement of (18)F-uptake. RESULTS: The inter- and intra-individual variations in (18)F-uptake (SUVA50%) were pronounced as 33.50 (range 4.42 to 37.92) and 27.18 (range 4.00 to 31.18), respectively. A significant correlation between the MAR and (18)F-uptake was found (r = 0.80, p = 0.017). There was a heterogeneous response after treatment varying from -2.20 to 4.53. CONCLUSIONS: Iliac (18)F-uptake was associated with the local MAR in myeloma patients. Furthermore, (18)F-fluoride-PET demonstrated the heterogeneity of in vivo bone formation, enabling monitoring during treatment.

[Granulomatous mastitis: a rare cause of breast swelling]. / Een zeldzame oorzaak van een mammagezwel: granulomateuze mastitis.

Three women, aged 37, 39 and 29 years, presented with unilateral painful swelling of the breast. Ultrasound revealed inflammation with abscess formation. Histological biopsies contained granulomatous tissue without necrosis. Corynebacterium species were cultured in the first two patients. All 3 patients were diagnosed with granulomatous mastitis and were successfully treated with doxycycline. Granulomatous mastitis is a rare disorder that may mimic breast carcinoma. It occurs most frequently in fertile women. Diagnosis is based on histological biopsy which shows granulomas without necrosis, while other causes of granulomatous inflammation, especially tuberculosis, have been excluded. The aetiology is not fully understood. It is hypothesised that the granulomatous mastitis is caused by a type IV allergic reaction. Recently an association with Corynebacterium species was suggested. Best practice treatment methods are unclear. Most patients are treated with surgical intervention and steroids, but the rate of recurrence is high (50%). Treatment with doxycycline must be considered in patients with cultured Corynebacterium species.