Renal Cyst Disorders - Renal - Medbullets Step 1

Snapshot
A 26-year-old man presents to his primary care physician with abdominal and lower back pain. He reports to also seeing blood in his urine. Medical history is non-contributory. Family history is significant for his father requiring hemodialysis at a young age. Vitals signs are significant for a blood pressure of 162/112 mmHg. A renal ultrasound is performed and shown. (Adult polycystic kidney disease)
Adult Polycystic Kidney Disease (ADPCKD)
Clinical definition an inherited disorder that results in expansion of multiple renal cysts which ultimately leads to end-stage renal disease Epidemiology incidence the most common inherited cause of kidney disease demographics ≥ 30 years of age risk factors family history Pathogenesis PKD1 or PKD2 mutations results in abnormal cell signaling that results in cystogenesis expansion of cysts results in progressive loss of nephrons Genetics inheritance pattern autosomal dominant mutations PKD1 (on chromosome 16) or PKD2 (on chromosome 4) PKD1 encodes polycystin-1 PKD2 encodes polycystin-2 Associated conditions cyst development in other organs such as liver (most common extra-renal cyst type) pancreas seminal vesicle note, that kidneys appear normal at birth vascular abnormalities such as intracranial aneurysm coronary artery aneurysm cardiovascular abnormalities mitral valve prolapse left ventricular hypertrophy diverticulosis Prognosis with age the number and size of the cyst increases Presentation symptoms abdominal or flank pain low back pain hematuria recurrent urinary tract infections hypertension
Juvenile Polycystic Kidney Disease (ARPCKD)
Clinical definition a congenital fibrocystic disorder that results in renal and hepatic manifestations Epidemiology incidence 1 in 20,000 live births Pathogenesis PKHD1 gene mutation leads to abnormal production of fibrocystin and polyductin which results in defects of the renal tubular structures dilatation and elongation of collecting ducts bile duct structures cystic dilatation of intra- and extra-hepatic bile ducts Genetics inheritance pattern autosomal recessive mutation PKHD1 gene on chromosome 6 Associated conditions Potter sequence Presentation symptoms/physical exam bilateral abdominal mass in infants and children hepatomegaly in infants and children hypertension
Medullary Cystic Disease
Clinical definition an autosomal dominant inherited disorder that results in tubulointerstitial fibrosis of the kidney medullary cystic disease is characterized by autosomal dominant inheritance pattern progressive and slow impairment in renal function that ultimately results in end-stage renal disease no or minimal proteinuria with a bland urine sediment medullary cysts on renal ultrasound in most cases medullary cysts are not present can see shrunken kidneys on ultrasound