Low-grade appendiceal mucinous neoplasm with puffer ball-like appearance: A case report.

We report a case of ruptured low-grade appendiceal mucinous neoplasm with an impressive toy puffer ball-like appearance on magnetic resonance imaging. A 79-year-old woman with lower abdominal pain underwent computed tomography scanning, revealing a 6-cm mass in the right lower abdomen. T2-weighted images showed a radial low-signal structure in the central area of the mass, which was presumed to be fibrotic. Pathology confirmed ruptured low-grade appendiceal mucinous neoplasm. The rupture point was at the tip of the appendix, coinciding with the center of radial fibrosis. The unique morphology of the puffer ball-like appearance in this case may be a characteristic of low-grade appendiceal mucinous neoplasms.

A case of multicentric Castleman's disease with membranoproliferative glomerulonephritis type 3-like lesion.

Renal involvement is a significant complication of multicentric Castleman's disease (MCD) and various glomerular involvements have been reported. A 45-year-old Japanese man presented with persistent proteinuria, with lymphadenopathy and hypergammaglobulinemia. He had been diagnosed 4 years previously with MCD. As his renal impairment had progressed to renal failure, he underwent a renal biopsy. Histology revealed diffuse and global membranous lesions with large and heterogeneous epimembranous deposits. In addition, mesangial cell proliferation and focal extracapillary lesions were found. Under immunofluorescence, granular staining for anti-IgG, IgG1, IgG2 and IgA was strongly positive in the capillary loop, and weakly positive in the mesangium. As such, there was a diversity of histological features. Our perspective with regard to pathogenesis is that the formation of the immune-complex contributed to the membranoproliferative glomerulonephritis type 3-like lesion. This histological multiform with MCD is valuable for increasing our understanding of the mechanism for onset of immune-complex glomerular deposition and cellular proliferation of glomerulonephritis.

Acute and transient podocyte loss and proteinuria in preeclampsia.

Glomerular podocytes are known to regulate proteinuria and podocyturia correlated with proteinuria. Podocyturia, the urinary excretion of viable podocytes (glomerular epithelial cells), has been associated with proteinuria in preeclampsia. This study is the first to investigate the time course alterations of podocyturia in patients with preeclampsia (11 cases) and normotensive pregnant women (45 cases). Urinalysis was performed at 35 weeks of gestation, 4 days after delivery, and 1 month after delivery. In patients with preeclampsia, podocyturia was evident at 35 weeks of gestation and 4 days after delivery, while proteinuria had already decreased at 4 days after delivery. At 1 month after delivery, almost no patients exhibited podocyturia. In control cases, proteinuria was not significant throughout the study period. However, 9 of the 45 controls exhibited transient and mild podocyturia at 4 days after delivery without proteinuria or hypertension. Statistics indicated a correlation between urinary podocyte number and blood pressure, but not with proteinuria. In conclusion, podocyturia in preeclampsia is transient and almost synchronous with heavy proteinuria. The results suggest that acute podocyte loss implicates podocyturia as the possible mechanism of proteinuria in women with preeclampsia.

Secondary membranous glomerulonephritis associated with recipient residual lymphoma cells after allogeneic bone marrow transplantation.

A 29-year-old man with malignant lymphoma developed membranous nephropathy (MN) after allogeneic bone-marrow transplantation (BMT). There had been no obvious findings of graft versus host diseases (GVHD) after BMT, and the dosage of immunosuppressant drugs had not been reduced during this period. At the onset of MN, a few lymphoma cells still remained in the bone marrow; the patient achieved complete remission of MN after the disappearance of the lymphoma cells. In this case it is suggested that immune complexes including antigens expressed by lymphoma cells might induce MN. Therefore, this is a significant case that may reveal an alternative mechanism of the onset of MN related to BMT.

C4d Immunohistochemistry in glomerulonephritis with different antibodies.

BACKGROUND: The presence of C4d in the kidney is generally detected particularly for the diagnosis of antibody-mediated rejection in renal transplants. In frozen sections of immunofluorescence (IF) staining with anti-C4d monoclonal antibodies (mAbs), we noted intrinsic C4d deposition even in normal glomeruli though their pathogenic or an intrinsic role is unkown. An anti-C4d polyclonal antibody (C4dpAb), which is suitable for paraffin immunoperoxidase (IP) staining, is less used than mAbs, and it has demonstrated that intrinsic C4d is not evident. To establish a stable and reproducible procedure for C4d detection with the C4dpAb and to determine the staining characteristics of it, the present study aimed to test whether the method was comparable with IF with a mAb. METHODS: We compared the C4dpAb with the mAb in adjacent sections of human diseased kidneys, and then compared IP with IF of C4dpAb. Two ways of antigen retrieval was examined for IP. RESULTS: On comparing the two antibodies for glomerular staining with IF, we found that the pattern and intensity (C4dpAb showed intrinsic C4d with IF) were similar. In addition, C4dpAb staining with IP and IF demonstrated that the intrinsic staining in the normal glomerulus was mostly undetectable by IP, whereas IF showed distinct staining. Likewise, C4d deposition with IP in some cases was apparently weaker than that on IF, suggesting that this deposition is not intrinsic but indicates pathogenic complement activation. CONCLUSIONS: The advantage of the C4dpAb for immunohistochemistry is of value for reconsidering the role of C4d in glomerular diseases.

Carcinosarcoma of the liver producing granulocyte-colony stimulating factor.

An autopsy case of carcinosarcoma of the liver producing granulocyte-colony stimulating factor (G-CSF) is reported. The patient, a 74-year-old Japanese man, presented with multiple liver masses. His serum G-CSF was elevated to 286 pg/mL and a marked leukocytosis of 19 100/microL was observed. The patient had a rapidly aggravated clinical course and died 57 days after admission. Autopsy revealed a liver carcinosarcoma composed both of hepatocellular carcinoma (HCC) and sarcomatous elements immunoreactive with alpha-smooth muscle actin and desmin. Immunohistochemistry revealed positive staining of G-CSF in the cytoplasm of HCC, whereas none of the spindle cells was positively stained. Production of G-CSF was also confirmed by enzyme-linked immunosorbent assay, using the frozen tumor tissue taken at the autopsy. Similar to the majority of G-CSF-producing tumors in the literature, only the epithelial elements of the present case were immunopositive for G-CSF. Although a monoclonal origin of carcinosarcomas has generally been proposed, heterologous differentiation from a single clone might lead to the production of G-CSF only in the epithelial element in the present case. It is suggested that G-CSF was associated with the high-grade transformation of the epithelial elements, as well as the reported phenomenon of conventional HCC producing G-CSF.

[A resected case of stage IV gastric cancer successfully treated with TS-1/CDDP as neoadjuvant chemotherapy].

A resected case of gastric cancer is described. The patient was a 60-year-old woman who presented a type 3 gastric tumor complicated by invasion of the head of the pancreas and liver. Radical resection was not indicated, and we administered the following combination chemotherapy with TS-1 and CDDP. 120 mg/day of TS-1 was orally administered for 3 weeks followed by 2 drug-free weeks as 1 course and 9 5 mg (60 mg/m(2)) of CDDP was administered intravenously on day 8. After two courses, total gastrectomy and D2 lymph node dissection were performed. Radical surgery for cure was conducted. Microscopically, the histological effect was judged to be grade 1a. One year after the operation, the patient is still alive without recurrence and metastasis. TS-1/CDDP therapy is useful for advanced gastric cancer.

Early recurrence of dense deposit disease with marked endocapillary proliferation after renal transplantation.

Dense deposit disease (DDD), also known as type II membranoproliferative glomerulonephritis (MPGN), is characterized by the presence of continuous intramembranous dense deposits. At present, the histogenesis of DDD is not well known. Reported herein are two cases of early recurrence of DDD in renal allografts, with marked endocapillary proliferation. In case 1 the first allograft biopsy revealed electron-dense deposits mainly in the subendothelial and mesangial areas along with subepithelial humps, but a continuous intramembranous deposition was not obvious. In the sequential biopsy, the deposits were more often seen in the intramembranous area and finally formed a continuous osmiophilic substance, which is a characteristic feature of DDD. In case 2, continuous intramembranous deposition already coexisted with endocapillary proliferation at the first biopsy. In both cases, endocapillary proliferation was alleviated slightly as time progressed. The present report suggests that endocapillary proliferative glomerulonephritis is the earliest lesion in some cases of DDD. Detailed review of a clinical history and a subsequent follow-up biopsy should be done to distinguish these lesions from other types of endocapillary proliferative glomerulonephritis.

Membranous glomerulopathy induced by myeloperoxidase-anti-neutrophil cytoplasmic antibody-related crescentic glomerulonephritis.

A 68-year-old woman was referred for evaluation of nephrotic-range proteinuria and a course suggesting rapidly progressive glomerulonephritis. Serum anti-neutrophil cytoplasmic antibody against myeloperoxidase (MPO) was 204 U/ml. A renal biopsy specimen revealed necrotizing glomerulonephritis with crescent formation. However, immunofluorescence showed staining with IgG and C3 along capillary walls. IgG positivity included both IgG1 and IgG4. Electron microscopic examination disclosed both paramesangial and subepithelial deposits. This case suggests that rarely, MPO-ANCA-related crescentic glomerulonephritis may present nephrotic-range proteinuria and show immune deposits along capillary walls.

Peritubular capillaritis in early renal allograft is associated with the development of chronic rejection and chronic allograft nephropathy.

Peritubular capillaritis (PTCitis) has been recognized as one form of acute/active allograft rejection, and its relation to humoral immunity has been suggested. However, its mechanisms remain to be fully clarified, and there are no criteria for evaluating the extent of PTCitis in a biopsied allograft. In this study, we first evaluated the extent of PTCitis in early allografts in patients presenting with acute cellular rejection (ACR) and antibody-mediated rejection (AbAR). We also included patients who showed no evidence of ACR and/or AbAR. Next, we investigated whether or not PTCitis persisted and if peritubular capillary basement membrane (PTCBM) thickening was present in their follow-up biopsy specimens. We adopted the scoring system of PTCitis, which was presented at the Seventh Banff Conference on Allograft Pathology in 2003. In total, 53 patients were included in this study. At first biopsy, 17 showed ACR, eight showed AbAR, 16 showed mild PTCitis only, and 14 were without significant pathologic changes. The PTC score was the highest in the AbAR group, and in some patients the score gradually increased during the follow-up period. Similar changes were also observed in the group with mild PTCitis only. In late allografts, half of the patients with AbAR developed chronic rejection (CR), and the PTCBM score was the highest in that group. Surprisingly, CR was present in more than 30% of patients without ACR and/or AbAR but mild PTCitis only. In the control group, only a few showed CR and/or chronic allograft nephropathy (CAN). In conclusion, it became clear that we should carefully monitor for mild PTCitis in early allografts. In addition, our data also proved the usefulness of the PTC score and PTCBM score.

Renal graft loss with plasma cell-rich acute rejection in cadaveric renal transplantation: a case report.

We reported a case of renal graft loss in cadaveric renal transplantation. An episode biopsy with renal dysfunction showed plasma cell predominant inflammatory infiltration in the interstitium without a finding of vascular or glomerular rejection, and was diagnosed as plasma cell-rich acute rejection (PCAR). Despite intensive immunosuppressive therapy, the renal histology of repeated biopsies showed persistent plasma cell infiltration and the graft was finally lost. Immunohistological staining and immunoglobulin gene rearrangement studies to estimate the clonality of inflammatory cells revealed that the infiltrating plasma cells were polyclonal in origin. Epstein-Barr virus was not detected by in situ hybridization. From these results, we excluded the possibility of post-transplant lymphoproliferative disorder (PTLD); however, a precise definition and differential diagnosis between PCAR and PTLD has not yet been fully determined. As therapeutic regimens for PCAR and PTLD are different, definite guidelines for diagnosis and treatments of PCAR need to be established.

A patient with symptomatic osteomalacia associated with Fanconi syndrome.

We report a patient with renal tubulointerstitial fibrosis and symptomatic osteomalacia associated with Fanconi syndrome. A 55-year-old woman was hospitalized because of an inability to walk. Beginning approximately 2 years previously, she had experienced gradually worsening pain in the hips, shoulders, and trunk, culminating in a bedridden state. Serum urea nitrogen was 38 mg/dl; creatinine, 2.6 mg/dl; uric acid. 3.6 mg/dl; phosphate, 2.3 mg/dl; and alkaline phosphatase, 2111 IU/l. Urinary beta2 microglobulin was 72 331 microg/day. Aminoaciduria, renal glucosuria, and proximal renal tubular acidosis with a normal anion gap were also noted. The patient was diagnosed with Fanconi syndrome. Radiography demonstrated typical Looser zones in the proximal portion of the left and especially the right femoral shaft, and at several other sites. A renal biopsy specimen disclosed severe tubulointerstitial fibrosis with little cellular infiltration. Glomeruli were largely intact. A bone biopsy specimen indicated osteomalacia; no tetracycline labeling could be seen along most trabecular bone surfaces, and the ratio of total osteoid volume to bone volume was increased (71.8%). Bicarbonate administration (9 g/day) gradually lessened most symptoms, permitting ambulation. Calcitriol administration decreased excessive intact-parathyroid hormone emerging after 2 months of acidosis correction. Thus, severe acidosis associated with Fanconi syndrome can induce osteomalacia showing serious skeletal complications, but also responsiveness to bicarbonate therapy.

Sarcomatoid collecting duct carcinoma arising in the hemodialysis-associated acquired cystic kidney: an autopsy report.

A case of sarcomatoid collecting duct carcinoma (CDC) arising in a long-term hemodialysis-associated acquired cystic kidney was reported. A 71-year-old woman with a 21-year history of hemodialysis showed a peritoneal metastatic carcinoma (carcinomatous peritonitis) with an unknown primary site. An autopsy revealed a sarcomatoid collecting duct carcinoma of the right kidney with multicyst formation. In addition to the carcinomatous peritonitis, the tumor metastasized to the lymph nodes and bilateral lung. The primary tumor was composed of both carcinomatous and sarcomatous components, suggesting a high-grade transformation. Carcinomatous tumor cells were positive for epithelial membranous antigen (EMA), cytokeratin, and reactive to soybean agglutinin and peanut agglutinin, whereas the sarcomatous cells were positive for vimentin as well as EMA. Thus, the immunohistochemical and lectin-histochemical analysis confirmed that the tumor originated in the medullary collecting duct. Although CDC is not common in acquired cystic kidney disease patients, attention should be given to the occurrence of high-grade carcinoma of rare histological variant, as well as conventional renal cell carcinoma.