What causes leukopenia (reduced white blood cell count)?

The main causes of leukopenia (reduced white blood cell count) include the following: 1. **Drug side effects**: Long-term use of antibiotics, antineoplastic agents, and other medications may destroy white blood cells, leading to a decrease in their numbers. For example, drugs such as chloramphenicol, penicillin, and chemotherapy agents can affect the hematopoietic system and result in reduced white blood cell counts. 2. **Ionizing radiation**: Prolonged exposure to radiation can also destroy white blood cells. For instance, a decrease in white blood cell count commonly occurs during radiotherapy. 3. **Systemic diseases**: - **Infectious diseases**: Conditions such as pneumonia and the common cold may lead to excessive consumption of white blood cells during the immune response. - **Hematologic disorders**: Diseases such as aplastic anemia and leukemia can impair the production of neutrophils. - **Connective tissue diseases**: Conditions like systemic lupus erythematosus (SLE) can affect the hematopoietic system and lead to leukopenia in severe cases. When leukopenia is detected, prompt medical consultation is necessary to identify the underlying cause and initiate appropriate treatment.