D82.1

HCC Category Mapping

What This Code Means

A rare genetic disorder where the thymus gland (which produces immune cells) and parathyroid glands fail to develop properly, leading to immune deficiency and low calcium levels.

Coding Tips

• •This syndrome involves multiple organ systems; document cardiac defects, cleft palate, and hypocalcemia separately if present
• •Also known as 22q11 deletion syndrome; document associated conditions comprehensively for complete clinical documentation

Clinical Significance

DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a congenital immunodeficiency resulting from abnormal development of the third and fourth pharyngeal pouches, causing thymic hypoplasia or aplasia, parathyroid hypoplasia with hypocalcemia, conotruncal cardiac defects, and characteristic facial features. The immune deficiency primarily affects T-cell development due to absent or small thymus.

Documentation Requirements

• ✓Documentation must include genetic testing confirming 22q11.2 deletion (fluorescence in situ hybridization or chromosomal microarray), T-cell enumeration, cardiac evaluation results, calcium and parathyroid hormone levels, facial dysmorphology description, and developmental assessment.
• ✓Document the severity of immunodeficiency (complete vs.
• ✓partial DiGeorge) and all affected organ systems comprehensively.

Commonly Confused Codes