Search

A 75-year-old man with fever was diagnosed with alveolar hemorrhage. Antineutrophil cytoplasmic antibodies for myeloperoxidase and proteinase 3 were absent. He received corticosteroid therapy, which immediately improved his symptoms and chest radiological findings. After the discontinuation of corticosteroids, fever and general fatigue relapsed, and renal function deteriorated with hematuria and proteinuria. A nerve conduction study revealed mononeuritis multiplex. Renal biopsy demonstrated focal necrotizing crescentic glomerulonephritis with endocapillary proliferative lesions, immunofluorescence C3 deposits, and electron-microscopic subepithelial hump-like deposits. Nephritis-associated plasmin receptor (NAPlr) and plasmin activity, biomarkers of infection-related glomerulonephritis, were positive in glomeruli. Although pathological findings suggested infection-related glomerulonephritis (IRGN), clinical manifestations, such as alveolar hemorrhage and mononeuritis multiplex, suggested systemic small vessel vasculitis. After corticosteroid therapy, systemic symptoms disappeared, and the gradual amelioration of hematuria and proteinuria was observed. Based on the clinical symptoms for which steroid therapy was effective, the patient was considered to have systemic small vessel vasculitis, the etiology of which may have been associated with infection.

Glomerulopathy with fibronectin deposits (GFND) is a rare hereditary kidney disease with autosomal dominant inheritance. A 21-year-old woman who had been diagnosed with GFND 10 years ago was admitted for investigation of a rapid decline in her renal function, hemolytic anemia, and cardiac dysfunction. A renal biopsy showed GFND accompanied by extraglomerular vascular lesions. Comprehensive treatments against hypertension and anemia improved the renal function. Although there have been few reports of vascular lesions in GFND, we suspect that endothelial hyperpermeability resulting from hypertension caused the fibronectin deposition and narrowing of the extraglomerular vascular lumens, thereby accelerating hypertension and inducing hemolytic anemia.

Nephrotic syndrome (NS) rarely occurs in post-hematopoietic stem cell transplantation (HSCT) recipients but represents the renal manifestation of graft-versus-host disease (GVHD). Membranous nephropathy (MN) accounts for almost two thirds of post-HSCT NS and is caused by immune complex deposition. Renal thrombotic microangiopathy (TMA) without fulfillment of clinical criteria for TMA has been underreported because of reduced opportunity for histological examination. However, renal TMA has recently been reported in association with GVHD and humoral immunological reactions. Although both MN and TMA after HSCT are associated with GVHD and immunological abnormalities, these diseases are exceptionally coexistent in renal biopsy specimens. We herein describe a case of post-HSCT NS, histologically showing overlapped lesions of TMA and MN. Renal biopsy specimen after presentation of NS revealed early stage MN and TMA with evidence of chronicity. TMA was thought to have preceded MN, and renal biopsy at the phase of pre-nephrotic proteinuria might reveal earlier histological changes of isolated renal TMA. Detection of subclinical renal TMA earlier by spontaneous renal biopsy can help prevent progression of renal injury or overlapping of other renal pathologies. We also demonstrated Th2 predominant intraglomerular infiltration of lymphocytes by immunohistochemistry.

When we encounter glomerulonephritis of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides demonstrating many plasma cell infiltrations, histological overlapping of immunoglobulin G4-related disease (IgG4-RD) often comes into the differential diagnosis. No previous study has focused on the degree of plasma cells in the kidney infiltrate in ANCA-associated glomerulonephritis (ANCA-GN), and the significance of massive plasma cell infiltrate has not been investigated. To clarify the plasma cell ratio in renal biopsy specimens of ANCA-GN and the histological characteristic of “plasma cell-rich” ANCA-GN, 20 cases of ANCA-GN were reviewed and clinicopathologically analyzed. Plasma cell ratio was widely distributed between 1.4 and 81%, and the median ratio was 10%. Three patients were categorized in “plasma cell-rich” ANCA-GN, defined as over 45% plasma cell ratio. They tended to include many active glomerular lesions compared to chronic lesions and to display severe tubulointerstitial inflammation. It is suggested that plasma cell-rich ANCA-GN may be acute onset of the disease, and the target of early inflammation may also be in the tubulointerstitial region. Two of the three plasma cell-rich ANCA-GN cases demonstrated numerous IgG4+ cells, but no bird’s-eye pattern fibrosis or obliterative phlebitis. Plasma cell-rich ANCA-GN is not rare and demonstrates distinct clinicopathological characteristics. This study also reminds us that the presence of the significant number of plasma cells in ANCA-GN, as such, is not a histological diagnostic basis for overlap ANCA-GN and IgG4-related disease.

Masuzawa N, Urasaki K, Okamoto M, Nobori S, Ushigome H, Yoshimura N, Yanagisawa A. Overlapped glomerular lesions of chronic rejection and recurrent lupus nephritis in transplanted kidney: a case report. Clin Transplant 2011: 25 (Suppl. 23): 49–52. © 2011 John Wiley & Sons A/S. Abstract: We describe a renal transplant recipient with systemic lupus erythematosus (SLE) who showed continuous proteinuria and low complement levels without clinical evidence of active SLE. Her first renal allograft biopsy, performed nine yr and eight months after transplantation, revealed unusual histological change of glomeruli, and it initially led us to make a contradictory diagnosis based on light and electron microscopic examinations. Diffuse global double- or multi-contour glomerular basement membrane was caused by chronic endothelial injury owing to chronic rejection, and mesangial proliferation associated with mesangial electron-dense deposit was a histological change characteristic of recurrent lupus nephritis (RLN). Immunofluorescence study displayed weak mesangial staining of IgM and C1q. We concluded that this case presented overlapped chronic rejection and RLN. Because both transplant nephropathy and lupus nephritis present constellations of various histologies, it is difficult to diagnose their overlap. Complete morphologic studies with both immunofluorescence and electron microscopic evaluations in addition to microscopic examination should be performed to elucidate complex histological findings.

The development of multiple large tophi in patients with gout is rare. We report magnetic resonance (MR) and histological features of large subcutaneous tophi in a 32-year-old male patient with no known arthritis. His subcutaneous lesions were confused with a neoplastic process, evaluated by MR imaging, and surgically excised after biopsy. The honeycomb-like appearance on the gadolinium-enhanced images may reflect the characteristic multilobular structure of the tophi composed of avascular urate deposits and surrounding vascularized granulation tissue.

A 57-year-old female presented with an abnormal Pap smear. Colposcopic examination of the cervix revealed white mucosa with erosion and several areas of black pigmentation. After a colposcopically directed biopsy and loop conization, radical hysterectomy and bilateral salpingo-oophorectomy with pelvic and paraaortic lymphadenectomy were performed. Pathological examination disclosed an invasive squamous cell carcinoma admixed with many dendritic melanocytes. Melanin granules were present within the melanocytes and tumor cells. Although similar tumors have been reported in other sites, this is the first report to our knowledge of a pigmented squamous cell carcinoma of the uterine cervix.

Reported herein is a gastric leiomyosarcoma, which, nowadays, is extremely rare. Attention was focused not only on pathological findings but also on the histological basis of magnetic resonance imaging (MRI) findings. The patient was a 29-year-old Japanese woman. Preoperative T2-weighted MRI showed a large high-intensity gastric tumor with isointense streaks. The tumor was a broad-based large polypoid lesion and histologically consisted of fascicles of spindled cells having eosinophilic cytoplasm and cigar-shaped nuclei. Immunoreactivity for several smooth muscle markers including desmin on tumor cells, low amplification of both c-kit and PDGFRA cDNA on polymerase chain reaction, and absence of c-kit gene mutation in exons 9 and 11 strongly suggested that the tumor was not a gastrointestinal stromal tumor but a true leiomyosarcoma. In vitro MRI of the fresh tumor was obtained to explain the radiological findings on a morphological basis. In vitro MRI clearly depicted the very high-intensity areas separated by radially extended isointense lines. This radiological finding corresponded best to the most characteristic histological feature, that is, linearly extended fascicles of the tumor cells often with myxedematous change separated by radially elongated thin fibrovascular stroma: in other words, spouting appearance.

A diffuse-type giant cell tumor (DGCT) of the paravertebral region is a rare condition characterized by an ill-demarcated mass with facet joint involvement. We describe a case of extra-articular DGCT of the paravertebral cervical region without association to the facet joint. A 51-year-old male presented with a headache. Diagnostic imaging showed a dumbbell-shaped mass with enlargement of the right intervertebral foramen between C6 and C7. The tumor was completely resected in multiple fragments with the suspicion that it was a schwannoma. Histologically the tumor consisted chiefly of mononuclear histiocytoid cells, foamy macrophages and multinucleated giant cells, which led to a diagnosis of DGCT. The case alerts one to be aware that DGCT may originate from a paravertebral location as a soft-tissue mass without facet joint involvement.