Cystic Diseases of the Kidney and Renal Pathology

Comprehensive vocabulary flashcards covering renal cystic diseases, nephrotic and nephritic syndromes, various types of glomerulonephritis, tubulointerstitial diseases, and benign and malignant tumors of the kidney, bladder, and testes based on clinical lecture notes.

Polycystic Kidney Disease (PKD)

A condition characterized by bilateral, large kidneys containing bulging, filtrate-filled pouches (cysts) caused by nephrons failing to connect to any collecting duct.

Cysts (Kidney)

Bulging, filtrate-filled pouches caused by a nephron not connecting to any collecting duct, leading to filtrate expansion.

Minimal Change Disease (MCD)

Also known as 'Foot Process Disease' or 'Nil Disease', it is a nephrotic syndrome where podocyte foot processes appear fused under electron microscopy.

Focal Segmental Glomerulosclerosis (FSGS)

A condition similar to Minimal Change Disease occurring in the young, characterized by damaged foot processes of podocytes, hyalinosis, and glomerular scar tissue (sclerosis).

Membranous Glomerulonephritis (MGN)

A condition accounting for >50\% of adult nephrotic syndrome, featuring many immune complex deposits and a thick basement membrane.

Membranoproliferative Glomerulonephritis (MPGN)

A syndrome where $65\%$ of cases present as nephrotic and $35\%$ are mixed nephrotic/nephritic, characterized by enlarged hypercellular lobulated glomeruli.

Post-Streptococcal Glomerulonephritis (PSGN)

A nephritic syndrome featuring diffusely swollen and cellular glomeruli, blood casts in collecting tubules, and edematous interstitial tissue showing leucocytic infiltration.

Rapidly Progressive Glomerulonephritis (RPGN)

A condition characterized by the formation of crescents in the glomeruli and compressed capillary tufts that are replaced by fibrous tissue.

Chronic Slowly Progressive Glomerulonephritis

Also known as End Stage Kidney, it presents as small, firm kidneys with a finely granular surface, adherent capsule, and sclerosed glomeruli.

Acute Pyelonephritis

A tubulointerstitial disease characterized by enlarged, swollen kidneys, abscess formation, suppurative inflammation (microabscesses), and neutrophil-filled tubules.

Chronic Pyelonephritis

Condition featuring tubular atrophy and dilation with 'thyroidization' (dilated tubules filled with eosinophilic material resembling thyroid colloid), fibrosis, and chronic inflammatory infiltrates.

Hydronephrosis

Enlargement of the kidney due to urine stasis, potentially leading to infection, stone formation, pyonepheosis, and chronic renal failure (CRF).

Angiomyolipoma (AML)

A benign kidney tumor composed of adipose tissue (yellow), smooth muscle cells (pink/tan), and thick-walled blood vessels (red-brown) that lack elastic fibers.

Renal Oncocytoma

A benign epithelial tumor originating from intercalated cells of the collecting duct, characterized by a mahogany-brown mass with a central stellate scar.

Clear Cell Renal Cell Carcinoma (ccRCC)

The most common RCC subtype ($70\% \text{ to } 80\%$), arising from the epithelium of convoluted tubules, appearing as a golden-yellow mass with characteristic 'chicken-wire' branching vasculature.

Chromophobe Renal Cell Carcinoma

A type of RCC ($5\% \text{ to } 7\%$ of cases) featuring large polygonal cells with pale cytoplasm (plant cell-like), perinuclear halos, and irregular 'raisinoid' nuclei.

Wilms Tumor (Nephroblastoma)

A pediatric triphasic malignant tumor consisting of blastemal (blue round cells), epithelial (primitive tubules), and stromal (spindle-shaped cells) components.

Urothelial Papilloma

A benign exophytic lesion (usually <1\,cm) with delicate fibrovascular cores and normal urothelium thickness ($3\text{ to } 7$ layers).

Urothelial Carcinoma in Situ (CIS)

A flat, high-grade neoplasm confined to the urothelium characterized by hyperchromatic nuclei, frequent mitoses, and lack of maturation from basal to superficial layers.

Low-Grade Papillary Urothelial Carcinoma

A tumor with papillary structures covered by more than seven layers of malignant transitional epithelium with mild cytologic atypia and low mitotic activity.

High-Grade Urothelial Carcinoma

A tumor showing marked nuclear atypia, loss of polarity, frequent mitoses, and an invasive component often infiltrating the lamina propria or muscularis propria.

Benign Prostatic Hyperplasia (BPH)

Hyperplasia of glands and fibromuscular stroma, featuring glands with double epithelial lining and inspissated luminal material called corpora amylacea.

Corpora Amylacea

Inspissated luminal material found within the cystically dilated glands of Benign Prostatic Hyperplasia.

Seminoma

A germ cell tumor (age $30\text{ to } 50$ years) containing large polyhedral cells arranged in sheets separated by thin fibrous septa infiltrated by mature lymphocytes.

Embryonal Carcinoma

An aggressive germ cell tumor (age $20\text{ to } 30$ years) presenting as a soft, friable mass with areas of hemorrhage and primitive malignant epithelial clefts.

Yolk Sac Tumor

A germ cell tumor occurring in infants and young children, characterized by glomeruloid structures called Schiller-Duval bodies.

Schiller-Duval Bodies

Glomeruloid structures characteristic of Yolk sac tumors under microscopic examination.

Choriocarcinoma

A highly aggressive germ cell tumor (age $10\text{ to } 30$ years) with high $\beta\text{-HCG}$ levels, consisting of malignant cytotrophoblastic and syncytiotrophoblastic cells.