Cracking the code of CATCH 22 !!!!!


Dr.Sree Lekshmi, Dr. Jayasree, Dr.Perraju, Dr. Aswin, Dr.Lekshmi, Dr. Smriti, (neo)Dr.Sheela Namboothiri. (Paed genetics) DrC Jayakumar 

Term AGA Male Ba born to a 26 year old primi mother with anomaly scan showing right sided aortic arch lead to amniocentesis for micro array and that which showed 22q11 deletion – Di George syndrome . 
Ba was born at 36W + 6 days of gestation emergency LSCS due to non progression . T Piece resuscitator with PEEP 6 was given as ba developed breathlessness even in the absence of asphyxia . At admission ba was noted to have hoarse cry . 
General examination showed dysmorphic facies with squared nasal tip , microstomia .

Auxology Weight – 3.08 Kg , Head Circumference – 35.5 cm , Length – 46 cm . Ba had tachypnoea, sub coastal retractions and grunting hence was started on CPAP with PEEP 6 . 
Xray Chest showed bilateral hazy lung fields suggestive of Type 2 respiratory distress syndrome . 
Ba was found to have low calcium levels Calcium – 7.19 mg/dl , 
Phosphorus – 7.2 mg/dl , 
Magnesium – 1.8 mg/dl , 
Para Thyroid hormone – 15.16 pg/ml , 
Albumin – 4.1 gm/dl 
IV calcium bolus supplementation was given . Followed Syrup Shelcal at 150mg / day and Rocalcitrol 0.25mg was given once daily . Serial monitoring of the calcium levels were done and syrup shelcal was gradually increased to 250mg / day . 
Echo done showed two Osteum Secundum ASD measuring 4 mm and 3 mm and multiple apical muscular VSDs with left to right shunt.

In view of thymic hypoplasia , initially it was decided to defer all the live vaccines . Later flow cytometry was done and it showed raised CD-8 values with decreased CD 3 and CD 4 values . Hence all birth vaccines were administered . 

DISCUSSION : 

Introduction – 

DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a genetic disorder caused the deletion of a small part of chromosome 22 at the q11.2 region. It affects multiple systems in the body and presents with a wide range of clinical features, varying from mild to severe. 
It is also part of a spectrum of disorders called CATCH 22, referring to the common features: 
• Cardiac defects (heart problems) 
• Abnormal facial features 
• Thymic hypoplasia (leading to immune deficiency) 
• Cleft palate 
• Hypocalcemia (low calcium levels) 

Key Features of DiGeorge Syndrome: 

1. Cardiac anomalies: Congenital heart defects, particularly involving the outflow tracts (e.g., Tetralogy of Fallot, interrupted aortic arch). 

2. Facial features: Characteristic facial appearance including low-set ears, wide-set eyes, small mouth, and a prominent nose. 

3. Immune system dysfunction: Due to underdevelopment or absence of the thymus, leading to problems with T-cell production and increased susceptibility to infections. 

4. Hypocalcemia: Caused underdeveloped parathyroid glands, leading to low calcium levels which can cause muscle spasms or seizures. 

5. Palatal defects: Cleft palate or other defects, which can affect feeding and speech. 

6. Developmental delays: Many individuals with DiGeorge syndrome may experience learning difficulties, developmental delays, and speech problems. 

7. Psychiatric issues: Increased risk of psychiatric disorders like schizophrenia and anxiety, particularly in adolescence or adulthood. 

Diagnosis – 

It is often made through a combination of clinical features and genetic testing, such as fluorescence in situ hybridization (FISH) or other methods to detect the 22q11.2 deletion. 

Management – 

Management of DiGeorge syndrome is multidisciplinary and focuses on treating the specific symptoms. This may include: • Surgery for heart defects or cleft palate • Calcium and vitamin D supplementation for hypocalcemia • Immune system support in severe cases of immune deficiency • Early intervention for developmental delays and speech therapy • Regular monitoring for psychiatric conditions Since it affects various body systems, patients often require coordinated care from cardiologists, immunologists, endocrinologists, and other specialists.