Klinefelter syndrome 

Pathology:

• Males and 47,XXY karyotype; 46,XY/47,XXY mosaicism. 
• Dysgenesis of the seminiferous tubules. 
• By adolescence, hyalinisation and fibrosis within the seminiferous tubules and Leydig cell function is impaired, resulting in hypogonadism. 

Clinical features 

• Gynaecomastia 
• Decreased facial and axillary hair/decreased hair distribution
• Small, firm testes. 
• Decreased penile length
• Tall stature → long leg length → androgen deficiency → lack of epiphyseal closure 
• Learning difficulties and behavioral disorders

Risk/complications:

• Increased risk of breast cancer 
• Type 2 diabetes 
• Osteoporosis

Investigation

Management:

• androgen replacement
• For infertility: ICSI (intracytoplasmic sperm injection) 

Instruction: Study the chromosome analysis report and answer the following question

1. Write down the karyotype.

1. Write down the phenotype.

1. Mention 3 (three) important clinical findings in such case.

1. Mention 3 (three) increased risks in such patient.