Related Experiment Video

Updated: Aug 19, 2026

Biochemical Measurement of Neonatal Hypoxia
13:13

Biochemical Measurement of Neonatal Hypoxia

Published on: August 24, 2011

Urinary excretion of HMMA in children

E G Walters1, D G Proctor, G H Elder

  • 1Department of Medical Biochemistry, University Hospital of Wales, Cardiff, UK.

Annals of Clinical Biochemistry
|January 1, 1989
PubMed

Insights

Urinary homovanillic acid (HMMA) excretion in children suspected of neuroblastoma decreases with age. Random urine samples are sufficient for initial HMMA assessment, simplifying diagnostic procedures.

Area of Science:

  • Pediatric Oncology
  • Clinical Chemistry
  • Biomarker Analysis

Background:

  • Neuroblastoma is a common childhood cancer requiring accurate diagnostic markers.
  • Homovanillic acid (HMMA), a catecholamine metabolite, is a key biomarker for neuroblastoma diagnosis.
  • Accurate measurement of HMMA is crucial for early detection and management in pediatric patients.

Purpose of the Study:

  • To evaluate the relationship between urinary HMMA excretion and age in children.
  • To determine the adequacy of random urine samples versus 24-hour collections for HMMA assessment.
  • To establish reference ranges for HMMA excretion across different pediatric age groups.

Main Methods:

  • Urinary HMMA levels were measured in 359 children (birth to 17 years) suspected of neuroblastoma.
  • Measurements utilized both 24-hour urine collections (n=246) and random urine samples (n=113).
  • Urinary HMMA was analyzed relative to creatinine to account for urine concentration variations.

Main Results:

  • A progressive decline in urinary HMMA relative to creatinine was observed with increasing age.
  • Age-related decline allowed for combining statistical analysis groups after four years of age.
  • Similar ranges of HMMA values were obtained using both 24-hour and random urine collections.

Conclusions:

  • Urinary HMMA excretion decreases significantly with age in children.
  • Random urine samples provide adequate data for the initial assessment of HMMA excretion in children.
  • This finding simplifies the diagnostic approach for suspected neuroblastoma in pediatric populations.

More Related Videos

A Convenient Method for Extraction and Analysis with High-Pressure Liquid Chromatography of Catecholamine Neurotransmitters and Their Metabolites13:35

A Convenient Method for Extraction and Analysis with High-Pressure Liquid Chromatography of Catecholamine Neurotransmitters and Their Metabolites

Published on: March 1, 2018

Handheld Metal Detector Screening for Metallic Foreign Body Ingestion in Children04:55

Handheld Metal Detector Screening for Metallic Foreign Body Ingestion in Children

Published on: September 11, 2018

Related Concept Videos

Comparative Excretory Systems02:24

Comparative Excretory Systems

Animals have evolved different strategies for excretion, the removal of waste from the body. Most waste must be dissolved in water to be excreted, so an animal’s excretory strategy directly affects its water balance.
Drug Excretion: Miscellaneous Routes01:10

Drug Excretion: Miscellaneous Routes

Drug excretion involves various organs, including the liver, intestines, skin, and eyes. In the case of drugs or toxins, they can be actively secreted into bile by transporters in the hepatocyte's canalicular membrane. These substances enter the GI tract during digestion and may be reabsorbed into the body from the intestine. This process, known as enterohepatic recycling, can significantly prolong the presence and effects of a substance in the body. To interrupt this cycle, specific substances...
Pharmacokinetics in Pediatric Patients: Drug Metabolism01:24

Pharmacokinetics in Pediatric Patients: Drug Metabolism

In pediatric care, understanding the nuances of hepatic drug metabolism is crucial, as it significantly differs from that of adults. This divergence is primarily due to the developmental stage of drug-metabolizing enzymes, which affects how medications are processed in the body. In neonates, for instance, the activity of Phase I enzymes—critical for the initial breakdown of drugs—is markedly reduced, functioning at just 20–40% of the levels seen in adults. This reduction poses a challenge in...
Pharmacokinetics in Pediatric Patients: Drug Excretion01:26

Pharmacokinetics in Pediatric Patients: Drug Excretion

In pediatric medicine, understanding the renal function and drug elimination nuances is crucial for administering safe and effective treatments. Newborns, in particular, display markedly slower renal functions than adults, profoundly affecting how drugs are cleared from their bodies. This slower drug clearance requires clinicians to extend the dosing intervals for many medications to prevent drug accumulation and toxicity while ensuring therapeutic efficacy.One key area where these adjustments...
Urine Studies I: Urinalysis01:29

Urine Studies I: Urinalysis

Urinalysis is a widely used diagnostic test that analyzes urine's physical, chemical, and microscopic characteristics. Healthcare providers use it to detect and monitor various health conditions, including renal disease, urinary tract infections (UTIs), diabetes, and metabolic or systemic disorders.Components of UrinalysisUrinalysis consists of three primary components: physical, chemical, and microscopic examination. Each provides unique insights into the urine sample and, by extension, the...
Microbiota of the Urogenital Tract01:28

Microbiota of the Urogenital Tract

The human urogenital system, once thought to be sterile in healthy individuals, is now recognized as a complex microbial habitat. Advancements in molecular sequencing techniques have revealed that even in healthy adults, the kidneys and bladder harbor microbial populations similar to those found in the distal urethra, albeit in much lower abundance. These resident microorganisms, while generally innocuous, can become opportunistic pathogens under conditions that alter the urogenital...