ICD-10-CM > D50-D89 > D80-D89 > D84 > D84.8 > D84.82 > D84.822 D84.822 Immunodeficiency due to external causes Billable/Specific Copy Code Copy Description Code Also , if applicable, radiological procedure and radiotherapy (Y84.2) Use Additional code for external cause such as:exposure to ionizing radiation (W88)