2 Case Reports in Hematology Figure 1: Chest X-ray on day 14 after chemotherapy (ANC was less than 100 cell/µL). Figure 3: Chest X-ray day 22 after chemotherapy (ANC was 11,500 cell/µL). Figure 2: Chest X-ray day 18 after chemotherapy (ANC was 1100 cell/µL). Figure 4: Chest X-ray day 31 after chemotherapy (ANC was 6700 cell/µL). immune system, the diagnosis of paradoxical immune recon- stitution syndrome was made, and we started him on methylprednisolone 125 mg IV q 6 hours. Within 48 hours, his fever trended down and we were able to start weaning his oxygen requirements despite no signiﬁcant change in his CXR (actually CXR did not show a signiﬁcant change until 10 days later). After one week, we tapered his steroids down to pred- nisone 40 mg daily, antibiotics were continued for two weeks, patient was extubated successfully after 18 days of intubation, and CXR day 31 after chemotherapy is shown (Figure 4). He was transferred to the ﬂoor, and physical therapy was started. Prednisone was gradually tapered to continue a total period of three weeks of steroids therapy. Patient was discharged to a medical facility to continue occupational and physical therapy. 2. Discussion 2.1. Deﬁnition. Immune reconstitution inﬂammatory syn- drome is an exaggerated and dysregulated inﬂammatory response to invading microorganisms. It manifests when a rapid shift of host immunity from an anti-inﬂammatory and immunosuppressive state towards a pathogenic proinﬂam- matory state occurs. Immune reconstitution inﬂammatory syndrome gained increased recognition in HIV patients receiving antiretroviral therapy (ART). IRIS manifests in one of two forms: unmasking IRIS occurs as a result of reconstitution of adaptive or innate immunity to an antigen or pathogen, with the disease or infection becoming clinically apparent. In contrast, paradox- ical IRIS denotes a worsening of an already diagnosed clinical disease which applies to our patient. Incidence, risk factors, clinical features, and management of neutrophil recovery-associated IRIS are not as well pub- lished as in HIV-associated IRIS; therefore, throughout the discussion of our case, we will compare and contrast clinical data between these two entities. 2.2. Epidemiology. IRIS was described before the HIV epi- demic in patients receiving therapy for tuberculosis [1], but it became much more evident after the introduction