Pena-Shokeir syndrome

The Pena Shokeir syndrome (PSS) is an autosomal recessive non aneuploidic condition with some clinical features being similar to that of trisomy 18. The condition is most often lethal. 

Epidemiology

The estimated incidence is at ~ 1 in 12,000 births.

Clinical features

Features include ^2,4

• arthrogryposis which may in turn given many additional features such as 
  • rockerbottom feet
  • clenched hands
  • webbing over joints
• facial anomalies  : thought to be due to fetal akinesia ⁵
  • micrognathia
• camptodactyly
• polyhydramnios
• pulmonary hypoplasia
• intra-uterine growth restriction (IUGR)

Pathology

Some consider the syndrome to be of two distinct types

• Pena Shokeir syndrome type I : some publications consider this to fall under the same spectrum of the fetal akinesia sequence
• Pena Shokeir syndrome type II : 

Associations

• short umbilical cord ¹¹

Radiographic features

Antenatal ultrasound

May show many of the above features. Some sonographic features may be detected as early as 16 - 18 weeks ⁸.  

Etymology

It was initially described by S D J Pena and  M H K Shokeir in 1974 ⁹.

Prognosis

The prognosis is very poor with ~ 30% of cases being stillborn, and ~ another 40% not surviving past the first few weeks and with the remainder not surviving beyond a few months. There may be a recurrence rate of ~ 10 - 15 % for future pregnancies.

Differential diagnosis

General differential considerations include ⁸

• trisomy 18
• Neu-Laxova syndrome
• multiple pterygium syndrome
• Larsen syndrome
• Potter sequence : typically has oligohydramnios