Waardenburg syndrome (WS) is a rare genetic disorder characterized by congenital sensorineural hearing loss and pigmentary abnormalities, accounting for 2-5% of congenital deafness. While molecular testing is the diagnostic gold standard, clinical recognition remains crucial in low-resource or conflict-affected environments where specialized services are unavailable. We report a Syrian male in his early 20s who presented to the otorhinolaryngology clinic seeking exemption from military service, citing long-standing right-sided hearing loss. The patient and his family had never pursued medical evaluation for his pigmentary features or hearing problem. Examination revealed a white forelock, heterochromia iridis, synophrys, broad nasal root, and dystopia canthorum (W Index 2.2). Pure-tone audiometry demonstrated severe unilateral sensorineural hearing loss. Systematic neurological, ophthalmological, and musculoskeletal assessments were normal. Due to the lack of access to genetic testing, a clinical diagnosis of WS type I was made, and the patient was referred for genetic counseling. This case highlights diagnostic challenges in conflict-affected, resource-limited settings. Despite striking phenotypic features, the patient remained undiagnosed until adulthood. Missed opportunities included the absence of childhood hearing screening, delayed recognition of pigmentary signs, and a lack of educational or psychosocial support. Literature indicates that phenotypic diagnosis is reliable when multiple major criteria are present, yet diagnostic delays significantly affect quality of life. This report underscores the importance of timely recognition of WS in low-resource contexts. Strengthening primary care awareness, implementing basic audiological and pigmentary screening, and integrating psychosocial support may help mitigate diagnostic delays and improve long-term outcomes for patients with rare genetic disorders.

Waardenburg syndrome (WS) is a rare genetic disorder that affects both hearing and pigmentation. The wide divergence of WS poses significant diagnostic and management challenges. This study investigated type 4 WS within an underrepresented Mongolian population. Whole-exome sequencing revealed that two unique heterozygous variants were identified in the SOX10 gene: c.393C>G (p.Asn131Lys) in a five-year-old female patient presenting with profound sensorineural hearing loss (SNHL), dystopia canthorum, and a white forelock; and c.535A>T (p.Lys179Ter) in a nine-year-old male patient presenting with profound SNHL, dystopia canthorum, and Hirschsprung's disease. Temporal bone imaging revealed abnormalities in the inner ear structure in both patients. The genotypic and phenotypic characteristics were meticulously delineated, incorporating the deleterious effects of these variants, as evaluated by multiple predictive tools and the American College of Medical Genetics and Genomics (ACMG) criteria. In addition, structural characterizations were also presented using AlphaFold. The findings of this study contribute valuable genetic data to the limited literature on type 4 WS within this ethnic group and highlight the importance of genetic testing and multidisciplinary care for this rare disorder in settings with limited resources.

Waardenburg syndrome (WS) is a rare genetic disorder mainly characterized by hearing loss and pigmentary abnormalities. Currently, seven causative genes have been identified for WS, but clinical genetic testing results show that 38.9% of WS patients remain molecularly unexplained. In this study, we performed multi-data integration analysis through protein-protein interaction and phenotype-similarity to comprehensively decipher the potential causative factors of undiagnosed WS. In addition, we explored the association between genotypes and phenotypes in WS with the manually collected 443 cases from published literature. We predicted two possible WS pathogenic genes (KIT, CHD7) through multi-data integration analysis, which were further supported by gene expression profiles in single cells and phenotypes in gene knockout mouse. We also predicted twenty, seven, and five potential WS pathogenic variations in gene PAX3, MITF, and SOX10, respectively. Genotype-phenotype association analysis showed that white forelock and telecanthus were dominantly present in patients with PAX3 variants; skin freckles and premature graying of hair were more frequently observed in cases with MITF variants; while aganglionic megacolon and constipation occurred more often in those with SOX10 variants. Patients with variations of PAX3 and MITF were more likely to have synophrys and broad nasal root. Iris pigmentary abnormality was more common in patients with variations of PAX3 and SOX10. Moreover, we found that patients with variants of SOX10 had a higher risk of suffering from auditory system diseases and nervous system diseases, which were closely associated with the high expression abundance of SOX10 in ear tissues and brain tissues. Our study provides new insights into the potential causative factors of WS and an alternative way to explore clinically undiagnosed cases, which will promote clinical diagnosis and genetic counseling. However, the two potential disease-causing genes (KIT, CHD7) and 32 potential pathogenic variants (PAX3: 20, MITF: 7, SOX10: 5) predicted by multi-data integration in this study are all computational predictions and need to be further verified through experiments in follow-up research.

Waardenburg syndrome (WS) is an autosomal dominant genetic disorder characterized by the absence of melanocytes, leading to distinctive pigmentary abnormalities and sensorineural hearing loss. This case report describes extremely rare concurrent anomalies in a preterm male infant diagnosed with WS type 1. The newborn, delivered prematurely at 35 weeks due to maternal complications, presented with multiple congenital anomalies and required immediate resuscitation. He exhibited hallmark features of WS, including a white forelock, dystopia canthorum, and bilateral sensorineural hearing loss. Genetic testing confirmed a PAX3 gene mutation. The infant experienced significant respiratory and feeding challenges, necessitating intensive care. Management included mechanical ventilation, surfactant therapy, phototherapy for hyperbilirubinemia, and broad-spectrum antibiotics for suspected sepsis. The cardiac assessment revealed multiple anomalies, such as a patent foramen ovale and left ventricular hypertrophy, while renal ultrasound identified multicystic dysplastic kidney and bilateral hydronephrosis. Multidisciplinary care facilitated the infant's stabilization, transition to oral feeding, and ongoing specialized care. WS type 1 is associated with mutations in the PAX3 gene and presents with diverse clinical manifestations. Although renal and cardiac anomalies are uncommon in WS, their presence in this case underscores the complexity of the syndrome. Early intervention for hearing impairment and genetic counseling are critical for optimal outcomes. This report highlights the importance of a comprehensive and interdisciplinary approach to managing infants with WS, addressing both typical and atypical manifestations. It is worth noting that effective management of WS in neonates requires prompt identification and treatment of associated complications.

Researching Waardenburg syndrome (WS) underscores its rarity and complex symptomatology, presenting as a congenital disorder predominantly inherited in an autosomal dominant pattern. It exhibits incomplete penetrance, which results in a wide range of clinical manifestations, with variable phenotypic presentations within the same family as well. The most commonly found features are facial abnormalities, hypopigmentation of the skin, heterochromia iridis, and conductive deafness. Adding to the eccentricities of this syndrome are its four subtypes, each presenting with its specific clinical features, which helps in delineating the subtype. A mutated paired box 3 (PAX3​​​​​) gene manifests as type 1 Waardenburg, which is characterized by sideways displacement of the inner angles of the eyes (i.e., dystopia canthorum), widely spaced eyes, congenital sensorineural hearing impairment, and patchy pigmentation of the iris, skin, and hair. Due to insufficient research, it has been difficult to isolate all the genetic mutations responsible for type 2, but its phenotype is very similar to type 1 with minor differences. Type 3 is characterized by musculoskeletal abnormalities. Waardenburg-Shah syndrome (type 4), which is associated with Hirschsprung disease, is the rarest subtype and is caused by genetic mutations in the endothelin receptor type B (EDNRB), endothelin-3 (EDN3), or sex-determining region Y (SRY) box 10 (SOX10) gene. We present a case series of this unique subtype that presented with a typical history of constipation due to Hirschsprung disease and had phenotypic manifestations of white forelock, heterochromia iridis, and bilateral sensorineural hearing loss (SNHL). In parallel with a positive 1° family history of a white forelock, we reflect on the fundamentals of this unique syndrome, as well as its management protocols, highlighting the importance of genetic counseling and cultivation of a high index of suspicion for its diagnosis.