Early Onset Gout and Chronic Kidney Disease in a Young Female Patient

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Early Onset Gout and Chronic Kidney Disease in a Young Female Patient

Gout is often seen as a condition affecting older adults—particularly men—but when a 31-year-old woman walked into Peking Union Medical College Hospital in 2018, her 10-year battle with joint pain and kidney damage uncovered a rare genetic link that’s vital for young people with gout to understand.

A Decade of Pain and Declining Health

The woman’s journey began with a traumatic left ankle injury that triggered her first arthritis flare. Analgesics eased the pain quickly, but tests showed slightly elevated serum uric acid (sUA, a key marker for gout) and serum creatinine (SCr, a sign of kidney stress). Over time, joint pain returned—sparked by ankle strains or seafood—and worsened at night. Each flare brought rapid redness, swelling, and pain that lasted about a week. Eventually, her right ankle, wrists, and small hand/foot joints were affected—no trauma needed. A local clinic diagnosed gout and chronic kidney disease (CKD), and she took benzbromarone (a uric acid-lowering drug, stopped 8 years prior) and Shen shuai ning (a Chinese herbal remedy for CKD) intermittently.

But without close monitoring of sUA or SCr, her condition spiraled. Six years before her 2018 visit, hard, painless “tophi” (uric acid deposits) appeared on her ear, knees, and toes. Three years prior, she developed microcytic anemia (low hemoglobin, HGB = 78 g/L) while sUA hit 723 μmol/L and SCr rose to 184 μmol/L (eGFR = 36.53 mL/min/1.73 m²)—signaling worsening kidney function. Pain grew more frequent (monthly instead of every 2 months) and intense, lasting longer each time. By 2018, a severe left ankle flare left her unable to move, and short-term allopurinol (another uric acid drug) and a steroid shot offered only temporary relief.

Testing Uncovers a Genetic Clue

At Peking Union, exams revealed:

  • Obesity (BMI = 32.8 kg/m²) and high blood pressure (148/88 mmHg).
  • A red, swollen left ankle and tophi on her hands, feet, and ear.
  • Moderate anemia (HGB low), sUA = 847 μmol/L (normal for women: ~155–357 μmol/L), and SCr = 220 μmol/L (eGFR = 25 mL/min/1.73 m²—stage 4 CKD).
  • Urine tests showed low pH (5.0, which promotes uric acid buildup) and reduced uric acid excretion (fractional excretion of uric acid, FEUA = 3.8%).
  • Ultrasound found shrunken kidneys with a thickened cortex; dual-energy CT confirmed uric acid deposits in her joints.

Rheumatoid arthritis, lupus, and other causes were ruled out. Then, whole-exome sequencing (WES)—a test that reads nearly all genes—revealed a heterozygous UMOD gene mutation (c.586G>T, pD196Y). This mutation was also found in her 10-year-old daughter, who had normal kidney function but elevated sUA (>600 μmol/L). The diagnosis: autosomal dominant tubulointerstitial kidney disease (ADTKD-UMOD), a rare genetic disorder where faulty uromodulin (a kidney protein) builds up, damaging tubules and reducing uric acid excretion.

Treatment and Lessons Learned

The woman started:

  • A low-purine diet (avoiding organ meats, seafood, and alcohol).
  • Extra water and sodium bicarbonate to alkalize her urine (preventing uric acid stones).
  • Low-dose febuxostat (10 mg/day, increased to 20 mg/day) to lower uric acid—safer for her kidneys than NSAIDs.
  • Nifedipine for hypertension and iron supplements for anemia.

Results were promising: In 1 month, her HGB rose to 115 g/L, sUA dropped to 336.9 μmol/L, and SCr improved to 194.9 μmol/L. Six months later, her tophi shrank by over 50%. But when she stopped medications, her health crashed: HGB fell to 83 g/L, SCr rose to 222.3 μmol/L, and sUA spiked to 781.2 μmol/L. She restarted treatment—and the message was clear: ADTKD-UMOD requires lifelong management.

Why This Matters for Young People With Gout

ADTKD-UMOD (OMIM: 191845) is caused by UMOD mutations that disrupt uromodulin, a protein that protects kidney tubules. Symptoms include early-onset gout (from low uric acid excretion), slowly worsening kidney function, and often a family history—though this patient’s parents had no obvious issues. For young women with gout (a group where gout is rare), genetic testing is critical:

  • Her daughter, though asymptomatic now, carries the same mutation and has elevated uric acid. She’ll need lifelong monitoring to catch kidney or joint damage early.
  • Prenatal testing is recommended if she decides to have more children.

The Takeaway

Gout in young women shouldn’t be dismissed as “typical”—it may signal a genetic disorder like ADTKD-UMOD. Early testing, consistent uric acid-lowering therapy, and avoiding kidney-harming drugs can slow CKD progression and improve quality of life. For this patient, sticking to her treatment plan helped shrink tophi and ease pain—but stopping meds led to a rapid relapse. Her case is a stark reminder: Chronic conditions require chronic care.

This study was conducted by Yu Cao, Xin-Xin Han, Xiao-Xue Wang, Yun Zhang, and Xue-Jun Zeng from the Department of General Internal Medicine at Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College. The patient provided informed consent for her case to be published.

Funding: Capital Medical Development Research Fund (2018-1-4012) and National Natural Science Foundation of China (81901667).

doi.org/10.1097/CM9.0000000000001174

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