The aim of this study was to assess the clinical spectrum of immunorestitution disease (IRD) in hospitalized patients over a 12-month period. In nine of 18 patients who presented with clinical deterioration during reduction or cessation of immunosuppressants (n = 6) or bone marrow engraftment (n = 3), IRD cases included the following infections: scabies infestation (n = 1); gastric strongyloidiasis (n = 1); hepatosplenic candidiasis (n = 1); methicillin-resistant Staphylococcus aureus abscess formation (n = 2); polyomavirus-related hemorrhagic cystitis (n = 3); and influenza A pneumonitis (n = 1). Immunopathological damage during withdrawal of immunosuppression is an incidental way to uncover an asymptomatic infectious disease. Serial monitoring of hematological and clinical profiles is essential in making a diagnosis of IRD.