Introduction
Good’s syndrome(GS), a rare acquired immunodeficiency  condition, first described by Dr. Robert Good in 1954, is characterized by thymoma, hypogammaglobulinemia, and low peripheral B‑lymphocyte count. GS tend to occur in individuals aged 40‑60 years, resulting in increased risk of recurrent infections with kinds of conditionally pathogenic bacteria, viruses, and fungi[1, 2]. Almost half of GS patients suffer from chronic diarrhea due to opportunistic infections, such as Salmonella spp. , Campylobacter. jejuni , Clostridium difficile , andCytomegalovirus(CMV)[3-5]. CMV, a kind of encapsulated double-stranded DNA β-herpesvirus, is a common virus that can infect human beings. CMV could cause pneumonia, retinitis, encephalitis, and enteritis in GS patients[4, 6-14].We will report a female patient with GS and chronic diarrhea due to CMV infection and make a literature review of related cases to conclude the characteristics of this condition so as to decrease the misdiagnosis and delayed diagnosis and improve the clinical diagnosis and prognosis of this rare disease.