A Case Report on Vitamin C Supplementation in a 67-Year-Old Male with Leukopenia

Explore a case report on oral vitamin C supplementation and changes in white blood cell and neutrophil counts in a 67-year-old man with chronic leukopenia. CASI Editorial Team Jul 21, 2026 White blood cell (WBC) counts are among the most routinely ordered labs in clinical practice, and values that fall outside the standard range are often a cause for concern. Leukopenia is defined as a white blood cell count <4,000 cells/µL, while neutropenia refers to an absolute neutrophil count <1,500 cells/µL. Neutrophils make up the largest share of circulating leukocytes and are responsible for engulfing pathogens, so a shortage can weaken immune defenses. Neutropenia can arise from autoimmune conditions, infections, medication side effects, low folate, vitamin B12, or copper, or leukemia, among others. When the cause is unclear or the counts are severely abnormal, a bone marrow biopsy is often ordered to check whether neutrophil reserves are adequate. One explanation that often goes unconsidered is benign ethnic neutropenia (BEN), where lower neutrophil counts reflect genetic background rather than disease. On average, people of African descent carry a white blood cell count about 700 ...