Inheritance: autosomal recessive
Genes: MKKS

Hydrometrocolpos syndrome
Kaufman-McKusick syndrome
MKS

Vaginal atresia
Hydrometrocolpos
Polydactyly
Hypospadias
Genital abnormalities
Chordee
Cryptoprchidism
Congenital heart disease

McKusick-Kaufman Syndrome (MKKS)

Clinical Characteristics

General description (for patients):

McKusick-Kaufman syndrome (MKKS) is a developmental disorder of the genitalia.   Notable features include hydrometrocolpos (retained vaginal secretions) secondary to a vaginal membrane, while males may have penile deformities and undescended testes.  Extra digits and congenital heart disease may also occur in both sexes although these manifestations do not necessarily occur together and are not found in all patients.  Surgical removal of the vaginal membrane should be considered to avoid complications but does not necessarily restore fertility.

Medical description:  

Hydrometrocolpos resulting from a transverse vaginal membrane or vaginal atresia is the most distinctive finding in MKKS affected patients. Secretions accumulate leading to distension of the obstructed uterus in puberty or in infancy due to the influence of maternal hormones.  Males often have glandular hypospadias, micropenis, prominent scrotal raphe, chordee (penile curvature) and cryptorchidism. Both sexes may have polydactyly in one or more limbs. Congenital  heart disease including atrial/ventricular septal defect, tetralogy of Fallot, and patent ductus areteriosus may also be present.  Atresias throughout the gastrointestinal tract are uncommonly seen. The diagnosis can be made prenatally via ultrasound when abdominal distension is present.  Other mutations in the MKKS gene also cause some similar features, notably polydactyly, which also occurs in the Ellis-van Creveld  and the Bardet-Biedl syndromes found in the same population. The presence of pigmentary retinopathy in the latter can be distinguishing.

Genetics:

This autosomal recessive condition results from missense mutations in the MKKS gene on chromosome 20 (20p12p). Not all homozygous individuals have clinical disease (incomplete penetrance). Mutations in the same gene also cause Bardet-Biedel-6 (BBS6) syndrome. MKKS from a bp substitution (250C>T) occurs predominantly in the Lancaster County, PA population.


Treatment:

Surgical repair of the vaginal obstruction and drainage of the accumulated pelvic fluid is recommended. Polydactyly, syndactyly and congenital heart defects can also be surgically managed.  Diagnostic confusion can sometimes be resolved with routine surveillance for manifestations of BBS with growth and developmental assessments, ophthalmologic examinations, and electroretinograms (ERG).

Prognosis:

Quality of life and lifespan is variable depending upon the clinical features present in different individuals.

Ancillary treatments and support:

Dependent upon individual features.

Specialists and specialty centers:

Ophthalmologist, Obstetrician or Gynecologist.

References:

Stone, D.L., Agarwala, R., Schaffer, A.A., Weber, J.L, Vaske, D., and Oda, T., Chandrasekharappa, S.C., Francomano, C.A., and Biesecker, L.G.:  Genetic and physical mapping of the McKusick-Kaufman syndrome.  Hum. Mol. Genet. 7: 475-481, 1998. PubMed ID: 9467007

McKusick, V. A., Bauer, R. L., Koop, C. E., and Scott, R. B.:  Hydrometrocolpos as a simply inherited malformation. J.A.M.A. 189: 813-816, 1964. PubMed ID: 14172277

McKusick, V. A., Weilbaecher, R. G., and Gragg, G. W.:  Recessive inheritance of a congenital malformation syndrome. J.A.M.A. 204: 113-118, 1968. PubMed ID: 5694533

Resources:

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