Related Experiment Video
Updated: Aug 7, 2026
07:45
Estimation of Urinary Nanocrystals in Humans using Calcium Fluorophore Labeling and Nanoparticle Tracking Analysis
Published on: February 9, 2021
Ammonium acid urate urolithiasis in Japan
Hidetoshi Kuruma1, Takashi Arakawa, Seiichi Kubo
1Department of Urology, Jikei University School of Medicine, Tokyo, and Department of Urology, Sagamidai Hospital, Kanagawa, Japan. hkuruma@jikei.ac.jp
Summary
Ammonium acid urate (AAU) urolithiasis presents differently in Japanese patients. Pure AAU stones are linked to young, thin women, while mixed AAU stones affect middle-aged men, indicating distinct patient profiles.
Area of Science:
- Nephrology
- Urology
- Mineralogy
Background:
- Ammonium acid urate (AAU) calculi are uncommon in developed nations but prevalent in developing countries.
- Understanding the specific characteristics of AAU urolithiasis in diverse populations is crucial for effective management.
Purpose of the Study:
- To investigate the distinct features of ammonium acid urate (AAU) urolithiasis in Japanese patients.
- To differentiate between pure and mixed AAU calculi based on patient demographics and laboratory findings.
Main Methods:
- Retrospective review of 8664 urolithiasis cases treated between 1992 and 2001.
- Stone analysis using infrared spectrophotometry to identify AAU crystals.
- Classification of AAU calculi into pure and mixed types based on crystallographic findings.
Main Results:
- AAU crystals were found in 33 calculi (0.38%) from 29 patients.
- Pure AAU urolithiasis (10 patients) predominantly involved young, thin women.
- Mixed AAU urolithiasis (19 patients) was more common in middle-aged men, with trends of low serum protein, potassium, and urine pH.
Conclusions:
- Two distinct types of AAU urolithiasis were identified: pure and mixed.
- Each type exhibits unique patient characteristics and potential pathophysiological associations.
- Recognizing the specific type of AAU urolithiasis is vital for tailored patient care.
Related Concept Videos
01:30Urinary Tract Calculi III: Medical Management
The diagnosis of renal calculi involves several imaging techniques, including non-contrast CT scans and ultrasound. These methods help visualize kidney stones, assess their size and location, and detect possible obstructions. Additionally, Measuring urine pH is useful for diagnosing specific stone types, such as struvite (alkaline pH) and uric acid stones (acidic pH). Cystine stones are primarily linked to cystinuria, a genetic condition. A urinalysis helps detect blood in the urine (hematuria)...
01:25Urinary Tract Calculi VI: Surgical Management
Procedures for Kidney StonesMedical intervention is necessary when kidney stones or renal calculi are too large to pass spontaneously (typically greater than 5 millimeters) when stones are accompanied by symptomatic infection (such as fever or pyelonephritis), when they impair kidney function, or when they cause persistent symptoms like severe pain, nausea, or urinary retention. Additionally, patients with only one kidney or those who cannot be treated with medical management also require...
01:28Urinary Tract Calculi I: Introduction
Renal calculi, or kidney stones, are solid deposits of minerals and salts formed inside the kidneys. In medical terminology, "calculus" refers to the stone itself, while "lithiasis" describes the process of stone formation. Depending on their location within the urinary system, these stones may be classified as either urolithiasis, when situated within the urinary tract, or nephrolithiasis, when located within the kidneys. Each term signifies the specific impact of the stone.Predisposition...
01:27Urinary Tract Calculi IV: Nutrition Therapy and Prevention
Management of renal calculi focuses on effective strategies like tailored nutrition and hydration therapy. Adjusting diet and fluid intake reduces stone formation and recurrence, making these interventions simple yet powerful in kidney stone prevention and management.Understanding Kidney StonesKidney stones form when calcium, oxalate, uric acid, and cystine concentrate and crystallize in urine. Factors contributing to their formation include genetic predisposition, certain medical conditions,...
01:28Urinary Tract Calculi V: Nursing Management
AssessmentSubjective Data: Obtain a detailed health history, including any recent or chronic urinary tract infections, periods of immobilization, previous episodes of renal calculi, and medical conditions such as gout, benign prostatic hyperplasia, or hyperparathyroidism. Review the medication history for drugs that may influence stone formation, including allopurinol, analgesics, loop diuretics, or thiazide diuretics. Document the use of long-term indwelling catheters and any past surgical...
01:26Urinary Tract Calculi II: Pathophysiology and Clinical Manifestations
Renal calculi, commonly termed kidney stones, are crystalline solid masses that form in the kidneys but can occur at any point within the urinary system, encompassing the kidneys, ureters, bladder, and urethra.The pathophysiology of renal stones involves several key factors: supersaturation of the urine with stone-forming constituents, changes in urine pH, a decrease in urine volume, and the presence of substances that promote or inhibit stone formation.Supersaturation of Urine: This is the...