Nephro- Renal cysts & horseshoe kidney

What is an epithelium lined cavity filled with fluid or semisolid material primarily from renal tubular elements (rarely symptomatic & has little clinical significance)?

Renal cyst

What are generalized cystic diseases associated with?

Cysts throughout the medulla & cortex of both kidneys, can progress to ESRD

What age are renal cysts MC?

> 50 y/o

What is thin walled, filled with clear amber fluid, usually found at the outer cortex & accounts for 70% of all renal masses?

Simple cyst

How do simple cysts present?

Usually asx & found incidentally on US, normal PE

If large → flank pain, palpable

If infection → flank pain, malaise, fever, CVAT

What is the main concern for simple cysts?

Differentiate from malignancy, abscess, or PCKD using US or CT

What is the standard of care for a simple cyst that meets the criteria for being benign?

Periodic reevaluation

What helps determine cyst risk for malignancy?

Bosniak classification

What is the treatment for a lesion that is NOT consistent with a simple cyst?

Surgical exploration

Who can develop acquired renal cystic disease?

Dialysis pts or anyone with long standing renal failure

How does acquired renal cystic disease present?

Might c/o back pain or hematuria,

potential to progress to malignancy, will progress to ESRD

How is acquired renal cystic disease diagnosed?

US, CT

What is the treatment for acquired renal cystic disease?

Renal transplant / remove kidneys

What is the MC inherited kidney disease associated with ADPKD1 (MC) & ADPKD2 genes?

Autosomal dominant polycystic kidney disease (ADPKD)

What will half of ADPKD patients have by age 60?

ESRD

Which mutation in ADPKD has a slower progression and longer life expectancy?

PKD2

The following presentation is associated with what condition?

• MC 20-40 y/o

• PMHx of UTIs & nephrolithiasis; FHx in most

• Abd/flank pain

• painless hematuria

• HTN

• large kidneys may be palpable on exam

ADPKD

How do labs appear in ADPKD?

UA → hematuria, mild proteinuria

Normal Hgb & Hct,

GFR starts to dec as gross enlargement progresses

What imaging studies are used to dx ADPKD?

First US (confirms dx), then CT if unclear

What other conditions is ADPKD associated with?

Hepatic cysts, pancreatic cysts, splenic cysts, cerebral aneurysms, colonic diverticula, cardiac valvular abnormalities, inc risk for ectopic pregnancy

What are complications of ADPKD?

Renal infx & nephrolithiasis

How does an ADPKD patient with a renal infection present?

Flank pain, fever, leukocytosis, positive blood cultures, & increased wall thickness on CT

What is the treatment for a renal infection in a patient with ADPKD?

Abx → FQ

What is the treatment for nephrolithiasis in an ADPKD patient?

Hydration & pain control

What do half of ADPKD patients have at presentation, and most end up developing?

HTN

How should HTN be treated in ADPKD?

Aggressively w/ ACEis (lisinopril) and/or ARBS (losartan) to prolong time to ESRD

What are the BP goals in ADPKD patients?

< 130 / 85

If proteinuria > 1 g/day → < 125/75

What is a rare but severe complication of ADPKD?

Cerebral/intracranial aneurysms → subarachnoid hemorrhage

What screening for cerebral aneurysms is recommended for ADPKD?

Arteriography, CT or MRI

*unless FHX of stoke or undergoing elective surgery

What is the treatment for ADPKD?

No specific rx, monitor BP & renal function, renal US yearly, genetic counseling, screen for cerebral aneurysms

What should ADPKD patients avoid?

Contact sports & NSAIDs (can worsen renal function & potentiate hyperkalemia)

What is the MC form of fusion of the kidneys where the lower poles of both unite across the midline?

Horseshoe kidney

What is the best treatment for horseshoe kidneys?

Surgery

How is horseshoe kidney diagnosed?

DMSA, MCUG, DTPA, can be missed by US

Who is horseshoe kidney MC in?

Males, turner syndrome, trisomy 18

What complications are associated with horseshoe kidney?

VUR, abnormal vascular supply, stone & hydronephrosis, film’s tumor, HTN