Hypertrophic cardiomyopathy secondary to deficiency in lysosome-associated membrane protein-2: A case report

Abstract

BACKGROUND

Danon disease (DD), in which mutations in the X-linked lysosome-associated membrane protein-2 (LAMP-2) gene result in hypertrophic cardiomyopathy, is a rare disease, reported primarily in small samples or cases. However, with the development of cardiac magnetic resonance imaging and genetic technology in recent years, the number of reports has increased.

CASE SUMMARY

We report a case of DD in an adolescent male patient, confirmed by genetic testing. The patient was admitted to our hospital with complaints of a three-year history of chest tightness and shortness of breath. His preliminary clinical diagnosis is hypertrophic cardiomyopathy. Our report includes the patient’s clinical course from hospital admission to death, step-by-step diagnosis, treatment course, and noninvasive imaging features. We highlight how a noninvasive diagnostic approach, based solely on clinical and imaging “red flags” for DD, can be used to achieve a diagnosis of DD with a high degree of confidence.

CONCLUSION

DD is a very dangerous cardiomyopathy, and it is necessary to achieve early diagnosis and treatment.

Keywords: Danon disease; Lysosome-associated membrane protein-2 gene; Cardiomyopathy; Hypertrophy; Cardiac magnetic resonance imaging; Myocardial strain; Case report

Core Tip: Danon disease (DD) is a rare X-linked disorder caused by a deficiency of lysosome-associated membrane protein-2. DD is clinically characterized by severe cardiomyopathy, skeletal muscle disease, and intellectual disability. The most frequent high-risk form of DD is cardiomyopathy, which can result in arrhythmia(s), early-onset heart failure, and even sudden cardiac death. Our case report intents to raise the awareness of DD and improve the clinical suspicion of DD.