A novel TTC26 variant in a patient with hexadactyly, pituitary stalk interruption, hepatopathy, nephropathy, and bilateral lip-palate cleft: A case report and expansion of the phenotype

Biallelic pathogenic variants in the TTC26 gene are known to cause BRENS (biliary, renal, neurological, skeletal) syndrome, an ultra-rare autosomal recessive condition with only few patients published to date. BRENS syndrome is characterized by hexadactyly, severe neonatal cholestasis, and involvement of the brain, heart, and kidney, however the full phenotypic and genotypic spectrum is unknown. Here, we report on a previously undescribed homozygous intronic TTC26 variant (c.1006-5 T > C) in a patient showing some of the known TTC26-associated features like hexadactyly, hypopituitarism, hepatopathy, nephropathy, and congenital heart defect. Moreover, he presented with a suspected unilateral hearing loss and bilateral cleft lip-palate. The variant is considered to affect correct splicing by the loss of the canonical acceptor splice site and activation of a cryptic acceptor splice site. Hereby, our patient represents one additional patient with BRENS syndrome carrying a previously unreported TTC26 variant. Furthermore, we confirm the involvement of the pituitary gland to be a common clinical feature of the syndrome and broaden the clinical spectrum of TTC26 ciliopathy to include facial clefts and a probable hearing involvement.

Polydactyly of the Foot Diagnosed from a Minor Nail Problem

Polydactyly is one of the most common foot congenital anomalies. It is often detected immediately after birth, but the diagnosis can sometimes be delayed if the symptoms are less evident. A 2-year-old girl with a complaint of recurrent bleeding from the right toenail was diagnosed with foot polydactyly. She underwent corrective surgery, and her family was satisfied with the outcome. Although the diagnosis of polydactyly may be difficult in cases with minor nail problems, further radiographic evaluation will be needed for the improvement of the patient's quality of life.

Sporadic familial ulnar hexadactyly of all four limbs

BACKGROUND

Polydactyly belongs to skeletal anomalies and may be a symptom of more complex genetic syndromes.

MAIN OBSERVATION

We observed an index case of ulnar hexadactyly of all four limbs in a 20-year-old man from India with three more brothers affected in his family. No additional anomalies were observed. The diagnosis of a sporadic (ulnar) postaxial hexadactyly was made.

CONCLUSION

Sporadic postaxial hexadactyly is one of the most common polydactylies in humans. In contrast, in the dermatologic literature the condition has only rarely been described.

CONCLUSION

Presence of supernummary digits or toes, i.e. polydactyly, is seen occasionally in the dermatologic practise. The present case is extraordinary since all limbs were involved and the same was true for three of his brothers. If treatment is asked, hand surgery would be necessary.