Malignant renal neoplasms are common solid tumors in pediatric oncology practice. These include the common Wilms' tumor/nephroblastoma and the uncommon neoplasms such as clear-cell sarcoma of the kidney (CCSK), rhabdoid tumor, renal-cell carcinoma, and others. The aim of this study was to describe in detail the cytopathological features of the histopathologically proven uncommon pediatric renal tumors. Aspirates from Wilms' tumor, which are mesenchyme predominant, show clusters of spindle cells associated with the matrix material. Evidence of rhabdomyoblastic differentiation may be present. CCSK, classic subtype, is characterized by round to oval cells arranged perivascularly and also in sheets and clusters intimately associated with a metachromatic matrix mucopolysaccharide material better appreciated in May-Grunwald-Giemsa (MGG)-stained smears. The cells also have more abundant cytoplasm and may show nuclear grooves. Spindle-cell pattern of CCSK is difficult to diagnose on aspiration cytology. Renal-cell carcinoma of childhood shows similar cytological features as its adult counterpart. Rhabdoid tumor of the kidney is characterized by a monomorphic population of cells with abundant cytoplasm, eccentric nuclei with prominent nucleoli. Intrarenal yolk sac tumor is a rare neoplasm and shows severely pleomorphic cells on aspiration. Awareness of these entities is important for the practicing cytopathologist. Further, non-Wilms' renal malignant neoplasms must be distinguished from the common Wilms' tumor so that appropriate chemotherapy protocols may be instituted in cases where the tumor is in an advanced stage of malignancy.

A 51-year-old man presented with a rash consisting of papules and indurated plaques, which had been present for a few weeks. He had been diagnosed 1 year previously with stage B chronic lymphocytic leukaemia (CLL), and 3 months prior to presentation, he had finished a phase II clinical trial regimen of dexamethasone, lenalidomide and ofatumumab.

Omenn syndrome is a rare combined immunodeficiency mostly associated with RAG1 and RAG2 mutations; the clinical manifestations are well-described and include neonatal erythroderma. Mortality due to opportunistic infections is a serious risk, and a timely diagnosis with a skin biopsy is an important part of the diagnostic workup. We wish to highlight key clinical features of Omenn syndrome and discuss the relevance of a skin biopsy. Pediatric DermatologyCUTTS eT al.

The aim was to evaluate the role of a-smooth muscle actin (SMA) and collagen type IV as markers of chronicity in renal biopsies of IgA nephropathy patients and to correlate the degree of their interstitial expression with renal function as judged by serum creatinine. Renal biopsies from 29 clinically, histologically and immunologically confirmed cases of IgA nephropathy were reviewed to assess activity and chronicity indices. Immunohistochemical stains for α-SMA and collagen type IV was performed on 23 patients with adequate tissue available in the block. The interstitial expression of α-SMA and collagen type IV was then correlated with chronicity and activity indices, serum creatinine and 24 hours urinary protein. Pearson's coefficient of correlation, unpaired-t test were used for statistical analysis. α-SMA and collagen type IV were shown to be expressed in the interstitium in all 22 cases showing interstitital fibrosis. Both showed a similar distribution pattern with predominant periglomerular and peritubular positivity. The cases were divided into two groups (low and high grade) depending on the percentage of interstitial area showing positivity for these two antibodies. On statistical analysis, the expression of both a-smooth muscle actin and collagen type IV showed a striking correlation with the histological chronicity index (P<0.01). A positive correlation was also noted with the serum creatinine at the time of diagnosis. It is seen that an immunohistochemical approach to grading interstitial fibrosis as in this study is far simpler than the histological grading systems prevalent and is an important baseline prognostic indicator.

No abstract