Two weeks ago, a 40-year-old Thai male, with unknown underlying disease, had another episode of acute intermittent arthritis and was diagnosed of having chronic tophaceous gout with acute gout attack.

Laboratory investigation revealed BUN of 183 mg/dL and Cr of 15 mg/dL. He underwent ultrasonography of the KUB system to evaluate for occult KUB stones and other causes of renal failure.

The KUB ultrasonography images are shown above. 

Questions 

1. Please describe the ultrasonography of KUB findings

2. What is the provisional diagnosis? 

3. Please obtain complete history taking and physical examination relevant to the provisional diagnosis

4. Please give proper management, including give advise and family counceling to the patient 

ANSWERs

1. USG KUB findings

• Multiple various size of cystic lesions in both kidneys with internal septation. The cysts replace almost entire renal parenchyma.

2. Diagnosis 

- Differential diagnosis  included ADPKD, ARPKD, ADTKD-UMOD 

- Provisional diagnosis:  ADPKD (Autosomal dominant polycystic kidney disease)This patient had an enlarged kidney and multiple cystic lesions, including small hepatic cysts and semimal vesicle cysts.

3. Complete history taking and physical examination relevant to the provisional diagnosis

1) History taking

• Family history of ESRD (before 55 yrs suggest PKD1), ADPKD
• Complication:
  • Functional manifestations: Concentrating defect , reduced renal blood flow (nocturia)
  • HT (Target organ damage): Cardiac, Cerebrovascular, Arteriolosclerosis and glomerulosclerosis, Peripheral vascular disease
  • Flank pain (most common) 
  • Cyst hemorrhage Gross hematuria
  • Nephrolithiasis
  • Infection (Cyst infection)
  • Renal enlargement (Abdominal discomfort)

2) Physical examination

• Vital signs: high blood pressure
• HEENT : pale conjunctiva (ESRD)
• Heart: cardiomegaly
• Abdomen:  palpable kidney, hepatomegaly
• Ext: pitting edema
• N/S: flapping tremor, motor power

4. Proper management, including give advice and family counseling 

1) Management

• Indication for RRT: Uremia (High BUN - 183) 
  • Mode of RRT : KT (1st line) during waiting -> PD or HD
  • ESRD care
• Symptomatic Treatment
  • Pain control : 
    • NSAIDs should be avoided
      • Narcotic analgesia should be reserved for acute episode
  • Observe clinical cyst haemorrhage or infection
• Prevention of progression (กรณียังไม่ ESRD)
  • Control HT -> in early ADPKD (15-49 years of age, GFR >60 ml/min/1.73 m2), rigorous BP control (target range 95-110/60-75 mm Hg) was associated with slower increase in total kidney volume, faster eGFR decline during the first 4 months of treatment followed by a slower eGFR decline thereafter without an overall eGFR effect
  • Salt restriction NaCl < 5 g/day (Na < 2 g/day)
  • Low protein intake 0.75-1 g/kg/day
  • Regular exercise (non-collision, low-impact)
  • Frequent water intake (3L/day) - prevent stone, suppression of vasopressin
• Novel therapy
  • Vasopressin receptor antagonists (tolvaptan) - slowed the increase in kidney volume and decline in kidney function and lowered the frequency of ADPKD-related adverse events (kidney pain, hematuria, UTI)
  • mTOR inhibitors - slow cyst growth
  • Octreotide - slow cyst growth
• Treat acute gout attack, chronic tophaceous gout 

2) Advice and family counseling

• เป็นโรคที่มีการถ่ายทอดทางพันธุกรรม -> บุตรมีโอกาสเป็นโรค 50 %
• แนะนำญาติสายตรงมาตรวจ screening -> basic lab -> kidney function (Cr), CBC, USG KUB
• ปัจจุบันยังไม่มีการรักษาหายขาด เเละยังไม่เเนะนำตรวจ genetic mutation เพื่อคัดครอง
• โรคนี้ต้องเฝ้าระวังภาวะเเทรกซ้อนที่อันตราย เช่น ICA (intracerebral aneurysm) 

เรียงเรียงโดย นพ.กฤตณัฐ เตชพาหพงษ์ แพทย์ประจำบ้านชั้นปีที่ 2 กองอายุรกรรม รพ.ภูมิพลอดุลยเดช กรมแพทย์ทหารอากาศ 

Reference: Halvorson CR, Bremmer MS, Jacobs SC. Polycystic kidney disease: inheritance, pathophysiology, prognosis, and treatment. Int J Nephrol Renovasc Dis. 2010;3:69-83.