A Study of Focal and Segmental Glomerulosclerosis according to the Columbia Classification and Its Correlation with the Clinical Outcome

Introduction  Focal and segmental glomerulosclerosis (FSGS) is a leading cause of nephrotic syndrome in both adults and children. The "Columbia classification of FSGS" includes five variants; not otherwise specified (NOS), tip, perihilar, cellular, and collapsing variants that may have different prognostic and therapeutic implications. Materials and Methods  This is a retrospective study and was carried out in the Department of Histopathology, Apollo Hospitals, Hyderabad. Of a total of 11,691 kidney biopsies over a 7-year period, from 2006 to 2012, 824 cases were diagnosed as FSGS, of which 610 cases in which detailed clinical findings were available were included in this study. FSGS was then categorized according to the Columbia classification. Results  FSGS, NOS was the predominant histomorphological variant. Serum creatinine was significantly high in the collapsing variant, followed by NOS. Follow-up data was available for 103 cases,72.8% had complete remission, 10.6% had partial remission, and in 16.5 % there was no remission. Relapses were observed in 6.7% cases, two patients (1.9%) succumbed, and 4.8% cases progressed to chronic kidney disease. Conclusion  This study showed that perihilar variant was less prevalent, with tip and cellular variants being more prevalent in Indian subcontinent compared to Western literature. Collapsing variant was also less common.

Somatic Variants and Exon-Level Copy Number Changes in Five Hyperplastic Oral Leukoplakias

Oral leukoplakia (OL), an oral potentially malignant disorder, begins with a hyperplastic/hyperkeratotic stage at which no genome-scale somatic single nucleotide variant profiles have been described so far. We performed exome sequencing of five cases at this stage with no evidence of dysplasia to identify genetic alterations (exon-level copy number alterations, indels, and single nucleotide variants), their association with transcript levels, and relationship with oral cancer susceptibility. Pathway enrichment analysis of genes associated with tobacco chewing and age-related mutation signatures, transcripts with variants predicted to be functionally damaging and those with significantly altered levels all indicated the involvement of focal adhesion, ECM-receptor interactions, regulation of cytoskeleton, and DNA repair. Two novel mutations identified in FAT1 tumor suppressor gene were associated with decreased transcript levels. In addition, 16 expressed cancer driver genes contained functionally damaging variants. Many of the affected genes were also reported in dysplastic OL lesions. The presence of variants in cancer driver genes and those shared with oral dysplasias possibly provides a basis for further progression and increased susceptibility to oral cancer.

Renal lymphoma diagnosed on kidney biopsy presenting as acute kidney injury

Introduction:

Renal manifestations associated with hematolymphoid malignancies are known. Primary or secondary involvement of the kidney by lymphomatous infiltration has various clinical presentations. Acute kidney injury is not an uncommon finding in relation to lymphomatous interstitial infiltration proven on kidney biopsy. However, diagnosing it solely on renal biopsy remains a challenge and needs expertise and aid of immunohistochemistry as the prognosis is dismal.

Methods:

This is a retrospective study of kidney biopsy-proven cases of renal lymphoma presenting with acute kidney injury.

Results:

The study included 12 patients with ages ranging from 4 to 50 years who presented with serum creatinine ranging 2.1–9.6 mg%. Renal biopsy findings showed interstitial lymphomatous infiltrate. Two cases were diagnosed as primary lymphoma and the other 10 as secondary lymphomas. Among the 12 cases, nine were B-cell non-Hodgkin lymphoma, of which diffuse large B-cell lymphoma was diagnosed in six (50%), low-grade B-cell type in two (16.6%), chronic lymphocytic leukemia in one (8.3%), and three were T-cell-type. Two were acute T-cell lymphoblastic lymphoma and one other was a high-grade T-cell lymphoma. Four patients succumbed. The other four patients are alive; one is on chemotherapy, while two of them are on hemodialysis.

Conclusion:

Acute kidney injury as a presenting feature with lymphomatous infiltration of renal parenchyma is not uncommon. The patchy involvement makes it challenging on kidney biopsy with definitive diagnosis being made with the help of immunohistochemistry. Appropriate multidisciplinary involvement improves patient outcome.

Two unusual cases of microvascular thrombosis in the immediate posttransplant period

We present two unusual cases of microvascular thrombosis in the immediate posttransplant period resulting in graft loss. The first was a 20-year-old female with a cadaveric renal transplant with immediate graft dysfunction due to microthrombi of probable donor origin, with nonrecovery of renal function nine months' posttransplant. The second was a 23-year-old male with unrelated live kidney transplant with hyperacute rejection due to anti-endothelial antibodies.