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A homozygous CARD9 mutation in a Brazilian patient with deep dermatophytosis
Anete S Grumach1, Flavio de Queiroz-Telles, Mélanie Migaud
1Outpatient Group of Recurrent Infections, Faculty of Medicine ABC, Santo Andre, SP, Brazil, asgrumach@gmail.com.
Insights
This study identifies a novel CARD9 mutation causing deep fungal infections in an immunocompetent patient. This finding expands the understanding of genetic predispositions to deep dermatophytosis.
Area of Science:
- Immunology
- Medical Mycology
- Human Genetics
Background:
- Deep dermatophytosis typically affects immunocompromised individuals.
- Recent research links CARD9 (caspase recruitment domain-containing protein 9) deficiency to deep dermatophytosis in previously
- immunocompetent" patients.
Observation:
- A 24-year-old Brazilian male presented with persistent oral candidiasis from age 3.
- He developed ulcerative, painful skin lesions at age 11, initially on the face and spreading to the trunk.
- Trichophyton mentagrophytes was isolated from lesions, and antifungal treatments were ineffective.
Findings:
- A novel homozygous CARD9 mutation (R101L) was identified, impairing neutrophil fungal killing.
- The patient's family members showed varying carrier statuses for the mutation.
- This is the first reported case of CARD9 deficiency in Latin America.
Implications:
- Highlights CARD9 deficiency as a cause of deep dermatophytosis in immunocompetent individuals.
- Expands the genetic and geographic understanding of CARD9-related immunodeficiency.
- Suggests genetic screening for CARD9 mutations in unexplained deep fungal infections.
Abstract:
Deep dermatophytosis has been described in HIV and immunosuppressed patients. Recently, CARD9 (caspase recruitment domain-containing protein 9) deficiency has been reported in individuals with deep dermatophytosis previously classified as "immunocompetent". We report a 24-year-old Brazilian male patient with deep dermatophytosis born to an apparently non-consanguineous family. The symptoms started with oral candidiasis when he was 3 years old, persistent although treated. At 11 years old, well delimited, desquamative and pruriginous skin lesions appeared in the mandibular area; ketoconazole and itraconazole were introduced and maintained for 5 years. At 12 years of age, the lesions, which initially affected the face, started to spread to thoracic and back of the body (15 cm of diameter) and became ulcerative, secretive and painful. Terbinafine was introduced without any improvement. Trichophyton mentagrophytes was isolated from the skin lesions. A novel homozygous mutation in CARD9 (R101L) was identified in the patient, resulting in impaired neutrophil fungal killing. Both parents, one brother (with persistent superficial but not deep dermatophytosis) and one sister were heterozygous for this mutation, while another brother was found to be homozygous for the CARD9 wild-type allele. This is the first report of CARD9 deficiency in Latin America.
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