(11.03) Prader-Willi Syndrome- A rare disorder

Prader-Willi syndrome is a rare, complex, multi system genetic disorder that results in a behavioural, physical, and mental and problems. The present case presented in adolescent age with diabetes and diabetic foot but was diagnosed on detailed history and examination.

Case(s) Description :

Sixteen year old male child, known case of diabetes mellitus for 1 year, presented with uncontrolled blood glucose and ulcer over left foot with blackening of right toe. Patient was taking oral anti-diabetic and insulin. On detailed evaluation it was found that patient had non institutional delivery at 8.5 months, no spontaneous cry, and low birth weight of 1.2 kg, unable to breast feed, delayed milestones and started speaking at age of 9 years indicating developmental delay. At the age of around 6 years, patient started eating excess food with progressive weight gain. At age of 14 years patient had weight loss, 58 kg to 24 kg in 2 years and was diagnosed as Diabetes mellitus. Patient’s mother and maternal grandmother have diabetes mellitus and had 3 siblings who were healthy. Patient had autistic symptoms – not talking, can understand and follow commands and nocturnal enuresis was present.
Patient was conscious and cooperative with normal vitals, on examination he was having short stature (Height- 121 cm, MPH – 172.5 cm) along with hypertelorism, almond shaped upward slanting eyes, prominent upper incisors, present BMI of 17 kg/m². Patient had micropenis, small testis with sensorineural hearing loss. Patient had normal biochemical profile with reduced FSH (2.65IU/L), LH (0.03IU/L), and testosterone (48 ng/dl).  Based on the history and examination genetic testing for Prader Willi syndrome was done which revealed deletion of specific chromosomal region 15q11.2-q13 in the paternal allele which is causative of the above rare syndrome.

Discussion : Prader-Willi syndrome is rare disorder seen in 1 in 10,000 to 30,000 people worldwide. Clinical findings differ by age group. In childhood and adolescence patient presents with history of hypotonia and poor sucking reflex in neonatal period, developmental delays, hyperphagia with obesity, hypogonadism, short stature and/or type 2 DM. The above case presented to us had all the above features but was lean due to uncontrolled type 2 DM and the diagnosis was confirmed by genetic analysis.