Generic selectors
Exact matches only
Search in title
Search in content
Post Type Selectors
Filter by Categories
Book Review
Case Report
Case Series
Clinical Images
Clinical Images/Spotters
Current Issue
Editorial
Editorial Commentary
Fellow’s Corner
Guest Editorial
Images (Radiology/Radioisotope Scans/Fluoroscopy Images, etc.)
Invited Editorial Commentary
Invited Review
Invited Review - Genetics for the Pediatric Endocrinologist 3
Invited Review - Genetics for the Pediatric Endocrinologist 4
Invited Review - Genetics for the Pediatric Endocrinologist 5
Letter to Editor
Mini Review
News
News ISPAE elections
Obituary
Original Article
Ped-Endo-Journal Scan
Pediatric Endocrine Trainees Section (Open-Forum)
President’s Page
Generic selectors
Exact matches only
Search in title
Search in content
Post Type Selectors
Filter by Categories
Book Review
Case Report
Case Series
Clinical Images
Clinical Images/Spotters
Current Issue
Editorial
Editorial Commentary
Fellow’s Corner
Guest Editorial
Images (Radiology/Radioisotope Scans/Fluoroscopy Images, etc.)
Invited Editorial Commentary
Invited Review
Invited Review - Genetics for the Pediatric Endocrinologist 3
Invited Review - Genetics for the Pediatric Endocrinologist 4
Invited Review - Genetics for the Pediatric Endocrinologist 5
Letter to Editor
Mini Review
News
News ISPAE elections
Obituary
Original Article
Ped-Endo-Journal Scan
Pediatric Endocrine Trainees Section (Open-Forum)
President’s Page
Generic selectors
Exact matches only
Search in title
Search in content
Post Type Selectors
Filter by Categories
Book Review
Case Report
Case Series
Clinical Images
Clinical Images/Spotters
Current Issue
Editorial
Editorial Commentary
Fellow’s Corner
Guest Editorial
Images (Radiology/Radioisotope Scans/Fluoroscopy Images, etc.)
Invited Editorial Commentary
Invited Review
Invited Review - Genetics for the Pediatric Endocrinologist 3
Invited Review - Genetics for the Pediatric Endocrinologist 4
Invited Review - Genetics for the Pediatric Endocrinologist 5
Letter to Editor
Mini Review
News
News ISPAE elections
Obituary
Original Article
Ped-Endo-Journal Scan
Pediatric Endocrine Trainees Section (Open-Forum)
President’s Page
View/Download PDF

Translate this page into:

Clinical Images/Spotters
3 (
1
); 37-38
doi:
10.25259/JPED_17_2023

Metaphyseal dysplasia – An uncommon mimicker of rickets

Department of Pediatrics, Kerala Institute of Medical Sciences HEALTH, Thiruvananthapuram, Kerala, India
Department of Medical Genetics, MedGenome Labs, Bengaluru, Karnataka, India
Department of Orthopedics, KIMS HEALTH, Thiruvananthapuram, Kerala, India
Corresponding author: Sheeja Madhavan, Department of Pediatrics, Kerala Institute of Medical Sciences HEALTH, Thiruvananthapuram, Kerala, India. sheejmadhavan@gmail.com
Licence
This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, transform, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.

How to cite this article: Madhavan S, Nair NUN, Madhavilatha G, Krishnan V. Metaphyseal dysplasia – An uncommon mimicker of rickets. J Pediatr Endocrinol Diabetes 2023;3:37-8.

Abstract

Metaphyseal dysplasias are rare conditions of genetic origin with clinical features similar to rickets. Awareness of these conditions is warranted to avoid delay in diagnosis. It will also help avoid unnecessary treatment with vitamin D leading to toxicity. We report here a case of a toddler who presented with clinical and radiographic features of rickets, who was eventually identified as a case of autosomal recessive metaphyseal dysplasia, Spahr type (OMIM# 250400).

Keywords

Metaphyseal dysplasia
MMP13 gene
Vitamin D deficiency rickets
Metaphyseal anadysplasia
Metaphyseal chondrodysplasia Spahr type

CASE SUMMARY

A 10-month-old male infant was incidentally noted to have clinical features suggestive of rickets while hospitalized for bronchopneumonia. He was the first-born child of unrelated parents and was healthy, and thriving with normal developmental milestones attained to date. His weight was 8.1 kg (World Health Organization [WHO] Z-score –0.85), length was 75 cm (WHO Z-score +0.90), and head circumference was 45.5 cm (WHO Z-score: +0.41). He had wide wrists [Figure 1] and Harrison’s sulcus. His anterior fontanel was closed. The spine, hair, teeth, and nails were normal. The serum calcium was 9.9 mg/dL (normal range 8.8–10.8 mg/dL), phosphorus 6.5 mg/dL (normal range 3.7–5.6 mg/dL), alkaline phosphatase (ALP) 360 IU/mL (normal range 145–420 IU/L), and 25-hydroxyvitamin-D3 19 ng/mL (normal range 30–70 ng/mL). The X-ray of his wrists showed irregular widened metaphyses [Figure 2]. X-rays of the spine were unremarkable with no radiological evidence of osteopenia. He received therapeutic doses of vitamin D followed by prophylaxis to correct low vitamin D3 levels. On follow-up, clinical and radiological features of rickets persisted, without any biochemical evidence of rickets. This led to the consideration of a rickets mimicker like metaphyseal dysplasia. Parents were counseled and with their consent, genetic studies (exome sequencing by next-generation sequencing) were performed which detected compound heterozygous mutation in the MMP13 gene. Sanger sequencing of the identified variants in the parents suggested the possibility of autosomal recessive metaphyseal dysplasia Spahr type (MDST) in our patient.

Figure 1:
Clinical photograph showing wide wrists.
Figure 2:
The X-ray of wrists showing irregular widened metaphyses.

DISCUSSION

Clinical and radiological features of rickets with normal serum ALP and with poor response following vitamin D therapy should alert a physician to the possibility of a rickets mimicker, the most common of which is skeletal dysplasia. The three forms of metaphyseal chondrodysplasias with overlapping clinical features are MDST, metaphyseal chondrodysplasia Schmid type, and metaphyseal anadysplasia.[1,2]

MDST is a heterogeneous group of disorders caused by a recessive mutation in the MMP13 gene on chromosome 11q22.[3] The condition presents with abnormalities in skeletal growth and radiological features of rickets in the form of metaphyseal irregularities. Mild bone fragility may be a feature.

The early presentation in our child suggested the possibility of metaphyseal anadysplasia. However, clinical exome studies pointed to a diagnosis of MDST. The two compound heterozygous variants identified and reported in the index patient lie in the catalytic domain of the MMP13 protein. The genotype-phenotype correlation, parental segregation studies, and prediction data strongly suggest that the variant is pathogenic in this child.

Declaration of patient consent

Patient’s consent not required as patients identity is not disclosed or compromised.

Conflicts of interest

There are no conflicts of interest.

Use of artificial intelligence (AI)-Assisted technology for manuscript preparation

The author(s) confirms that there was no use of Artificial Intelligence (AI)-Assisted Technology for assisting in the writing or editing of the manuscript and no images were manipulated using AI.

Financial support and sponsorship

Nil.

References

  1. , , , , , , et al. Nosology and classification of genetic skeletal disorders: 2015 revision. Am J Med Genet A. 2015;167A:2869-92.
    [CrossRef] [PubMed] [Google Scholar]
  2. , , , , , , et al. Standards and guidelines for the interpretation of sequence variants: A joint consensus recommendation of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. Genet Med. 2015;17:405-24.
    [CrossRef] [PubMed] [Google Scholar]
  3. , , , , , , et al. MMP13 mutations are cause of recessive metaphyseal dysplasia, Spahr type. Am J Med Genet A. 2014;164A:1175-9.
    [CrossRef] [PubMed] [Google Scholar]

Fulltext Views
510

PDF downloads
487
View/Download PDF
Download Citations
BibTeX
RIS
Show Sections