Phosphoglucomutase 1 deficiency misdiagnosed as Laron syndrome

Seyit Ahmet Uçaktürk; Emre Özer; Ahmet Cevdet Ceylan; Eda Mengen

doi:10.1515/jpem-2025-0447

Article

Phosphoglucomutase 1 deficiency misdiagnosed as Laron syndrome

Seyit Ahmet Uçaktürk , Emre Özer , Ahmet Cevdet Ceylan and Eda Mengen

Published/Copyright: October 17, 2025

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From the journal Journal of Pediatric Endocrinology and Metabolism Volume 39 Issue 2

Abstract

Objectives

Protein glycosylation is a crucial process involving the addition of oligosaccharides to proteins, which plays a significant role in stabilizing proteins and mediating protein–protein interactions. Mutations in genes associated with glycosylation can lead to congenital disorders of glycosylation (CDG), resulting in multisystem disorders. One such example is phosphoglucomutase 1 (PGM1) -CDG, caused by a deficiency of the PGM1 enzyme. In this report, we describe a patient with PGM1-CDG who was initially misdiagnosed with growth hormone insensitivity and benefited from recombinant human insulin-like growth factor-1 (rhIGF-1) therapy.

Case presentation

A 2-year-11-month-old female patient, born to first-degree cousin parents, presented with hypoglycemia and short stature. Her physical examination revealed frontal bossing, infantile facial appearance, and short stature. Laboratory investigations revealed that basal and stimulated growth hormone levels were very high, IGF-1 was low, and the inadequate response to the IGF generation test was consistent with growth hormone insensitivity (GHI). The patient was started on rhIGF-1 therapy, resulting in significant height gain. Subsequently, the patient showed improvement in height with rhIGF-1 therapy. The patient, who had additional findings such as elevated creatine kinase (CK) and transaminase levels and cardiomyopathy, was diagnosed with PGM1-CDG.

Conclusions

This case highlights that PGM1-CDG can mimic clinical and laboratory findings of GHI. CDG diagnosis should be considered in cases with clinical and laboratory findings of GHI accompanied by multisystem disorders such as hepatopathy, elevated CK, and cardiomyopathy. This patient’s successful response to rhIGF-1 therapy highlights the potential benefits of targeted therapies in treating growth hormone-related disorders in patients.

Keywords: growth hormone insensitivity; phosphoglucomutase 1 deficiency; IGF-1

Corresponding Author: Seyit Ahmet Uçaktürk, Department of Pediatric Endocrinology, University of Health Sciences, Adana City Training and Research Hospital, Adana, Türkiye, E-mail: uahmet77@yahoo.com

Research ethics: As this is a case report, formal approval from an Ethics Committee was not required.
Informed consent: Informed consent for publication of case details was obtained from the patient’s parents.
Author contributions: Seyit Ahmet Uçaktürk, Eda Mengen: responsible for the patient’s medical care, literature search, interpreted the findings, agreed to the final version of the manuscript, and took full responsibility for the manuscript. Ahmet Cevdet Ceylan has conducted and interpreted genetic studies. All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
Use of Large Language Models, AI and Machine Learning Tools: None declared.
Conflict of interest: The authors state no conflict of interest.
Research funding: None declared.
Data availability: Data are available upon reasonable request.

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Received: 2025-08-09

Accepted: 2025-10-06

Published Online: 2025-10-17

Published in Print: 2026-02-24

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Articles in the same Issue

https://doi.org/10.1515/jpem-2025-0447

Keywords for this article

growth hormone insensitivity; phosphoglucomutase 1 deficiency; IGF-1