Acquired von Willebrand syndrome associated with plasma cell myeloma - a rare histopathological bone marrow image.

Acquired von Willebrand syndrome (AVWS) is a rare bleeding disorder that is associated with a variety of underlying diseases. We report a case of AVWS associated with plasma cell myeloma. The patient was a 57-year-old male with recurrent bleeding symptoms for a few months. Physical examination was normal. Laboratory studies revealed isolated prolongation of the activated partial thromboplastin time. His factor VIII activity, von Willebrand factor (VWF) Ag, and VWF activity were low. Bone marrow aspirate showed diffuse infiltration of atypical plasma cells and erythroid line hyperplasia.

Pigmented/melanocytic malignant perivascular epithelioid cell tumor with TFE3-SFPQ(PSF) rearrangement - a challenging diagnosis of PEComa family of tumors.

We here report a case of a distinct subtype of pigmented/melanocytic malignant PEComa with TFE3-SFPQ(PSF) rearrangement. The tumor involved the iliac region and clinically mimicked metastatic melanoma. The immunohistochemical assessment was supplemented with molecular studies including fluorescence in situ hybridization (FISH) and next-generation sequencing sarcoma panel (NGS). We also discuss the differential diagnosis of intraabdominal PEComas and emphasise the recent molecular reports on the TFE3 rearranged tumors.

Relative interstitial volume is correlated with renal function even in non-representative biopsy.

An useful renal biopsy should be representative, that is should contain a sufficient number of glomeruli. However, a non-representative biopsy could possibly provide some information. The aim of the study was to evaluate the relationship between interstitial expansion, glomerular sclerosis and renal function in such material. The material consisted of 28 renal biopsies containing less than 5 non-sclerosed glomeruli. For each case the percentage of completely sclerosed glomeruli was recorded. The relative interstitial volume was evaluated by point counting method. Clinical data as sex, age, serum creatinine and urea levels were included into analysis. The mean percentage of completely sclerosed glomeruli was 39.6%; mean relative interstitial volume was 29.6%. Creatinine level was strongly correlated to relative interstitial volume (R = 0.70), but the correlation of creatinine level to percentage of sclerosed glomeruli was much weaker (R = 0.38). The relationship between interstitial expansion and renal function is seen also in deficient biopsy material. The correlation of renal function with interstitial expansion is stronger the correlation of renal function with glomerular sclerosis. These findings can indicate that the better representation is responsible for stronger prognostic impact of interstitial lesions

Are CD34+ cells found in renal interstitial fibrosis?

BACKGROUND: The CD34 antigen is a marker of precursor myeloid cells and endothelial cells, but also of a subset of spindle cells. METHODS: To establish the possible role of CD34+ cells in the progression of glomerulonephritis, 30 renal biopsies were investigated. Immunohistochemistry for CD34 and smooth muscle actin (SMA) were performed by standard methods. The results were assessed semiquantitatively. The relative interstitial volume (RIV) was evaluated by the point counting method. Clinical data such as sex, age, serum creatinine and urea levels were taken into account. RESULTS: CD34+ spindle cells and SMA+ myofibroblasts were present in the renal interstitium in all but one case. In membranous, membranoproliferative and segmental-proliferative glomerulonephritis, CD34+ cells were seen in clusters, while in IgA nephropathy and in segmental and focal glomerulosclerosis, single, scattered cells were seen. The density of CD34+ cells showed a positive correlation with the myofibroblast density and the RIV. Serum creatinine and urea levels were associated with the RIV of the kidney and to a smaller degree with the number of myofibroblasts and CD34+ cells. CONCLUSION: These results show that in glomerulonephritis, CD34+ spindle cells appear in the interstitium. At present, their possible role can only be speculated.

Morphometric classification of hairy cell leukemia in bone marrow trephine biopsy.

OBJECTIVE: To analyze cytologic and histologic parameters in bone marrow trephine biopsy in an attempt to define heterogeneity of hairy cell leukemia cells. STUDY DESIGN: The study group consisted of 28 trephine biopsies. Immunohistochemistry for CD20 antigen was used. Image processing and measurements were performed with AnalySIS 3.0 image analysis system (Soft Imaging System GmbH, Germany) and custom built programs. For planimetric measurements of nuclei, automatic segmentation was implemented. The measured parameters were: surface area, perimeter, minimum, mean and maximum diameter, and a set of form factors. Relative volumes of bone trabeculae, adipose tissue, hematopoietic tissue and neoplastic infiltrate were assessed by the point counting method. Nuclear volume was measured by the point sampled intercept method. Bone marrow fibrosis was assessed using a curvilinear line test system. RESULTS: Significant variability of cell nuclei was found, and their classification into 3 types was possible. The relative frequency of those types was different in various cases and allowed subdivision of cases into 3 groups that differed in some clinical and histologic manifestations. CONCLUSION: The present study demonstrated the heterogeneity of cell populations of hairy cell leukemia.

Adrenal rest presenting as a renal cyst. A case report.

The report presents a 42-year old female patient, in whom a cyst of the left kidney was diagnosed. The clinical presentation and gross picture suggested a simple cyst. The lesion was removed surgically; in the cyst wall, histology revealed structures identical to normal adrenal cortex. Based of this observation, the final diagnosis was established as the so-called adrenal rest. Such lesions are not uncommon in the kidney, but what was extraordinary in the described case was the macroscopic presentation. Thus, in differential diagnosis of cystic lesions of the kidney one should also take into consideration adrenal developmental abnormalities. This may be of particular importance in cystic clear cell renal carcinomas, the structure of which is well known to resemble the adrenal cortex.