Takenouchi-Kosaki syndrome is an extremely rare inherited disease caused by a heterozygous de novo mutation in the cell division cycle 42 (CDC42) gene. Fewer than 20 cases have been reported in the literature since it was first identified in 2015.
It is characterized by macrothrombocytopenia, developmental delay, dysmorphic facies, and deafness. Facial features include hypertelorism, up-slanting palpebral fissures, low-set and small auricles, short philtrum, thin vermillion border, flat nasal bridge, and micrognathia.
Lymphopenia with resulting immunodeficiency, structural brain abnormalities, vascular malformations (liver hemangiomas), aortic aneurysms, splenomegaly, autoimmune hemolytic anemia, hypothyroidism, systemic inflammation, myelofibrosis, lymphedema, and eczema have been reported. Camptodactyly and clinodactyly may also be observed.
Takenouchi-Kosaki syndrome
Alerts and Notices
Synopsis

Codes
ICD10CM:
Q87.89 – Other specified congenital malformation syndromes, not elsewhere classified
SNOMEDCT:
1172685001 – Macrothrombocytopenia, lymphedema, developmental delay, facial dysmorphism, camptodactyly syndrome
Q87.89 – Other specified congenital malformation syndromes, not elsewhere classified
SNOMEDCT:
1172685001 – Macrothrombocytopenia, lymphedema, developmental delay, facial dysmorphism, camptodactyly syndrome
Look For
Subscription Required
Diagnostic Pearls
Subscription Required
Differential Diagnosis & Pitfalls
- Wiskott-Aldrich syndrome
- DOCK8 deficiency
- Noonan syndrome
- NOCARH syndrome
- Jacobsen syndrome
- DiGeorge syndrome
- Braddock-Carey syndrome
Best Tests
Subscription Required
Management Pearls
Subscription Required
Therapy
Subscription Required
References
Subscription Required
Last Reviewed:08/07/2022
Last Updated:08/08/2022
Last Updated:08/08/2022