John, Kevin John

Nosocomial infections pose an imminent challenge to hospitalized Coronavirus disease-19 (COVID-19) patients due to complex interplay of dysregulated immune response combined with immunomodulator therapy. In the pre-pandemic era, immunomodulatory therapy has shown benefit in certain autoimmune conditions with untamed inflammatory response. Efforts to recapitulate these immunomodulatory effects in COVID-19 patients has gained impetus and were followed by NIH COVID-19 expert panel recommendations. The current NIH guideline recommends interleukin-6 inhibitors (tocilizumab and sarilumab) and Janus kinase inhibitors (baricitinib and tofacitinib). Several landmark research trials like COVAVTA, EMPACTA, REMDACTA, STOP-COVID and COV BARRIER have detailed the various effects associated with administration of immunomodulators. The historical evidence of increased infection among patients receiving immunomodulators for autoimmune conditions, raised concerns regarding administration of immunomodulators in COVID-19 patients. The aim of this review article is to provide a comprehensive update on the currently available literature surrounding this issue. We reviewed 40 studies out of which 37 investigated IL-6 inhibitors and 3 investigated JAK inhibitors. Among the studies reviewed, the reported rates of nosocomial infections among the COVID-19 patients treated with immunomodulators were similar to patients receiving standard of care for COVID-19. However, these studies were not powered to assess the side effect profile of these medications. Immunomodulators, by dampening the pyrogenic response and inflammatory markers may delay detection of infections among the patients. This underscores the importance of long-term surveillance which are necessary to discover the potential risks associated with these agents.

Takotsubo cardiomyopathy or Takotsubo Syndrome (TTS) is a reversible left ventricular dysfunction syndrome that is increasingly being recognized. Recent advances in nuclear imaging have allowed us to study TTS in greater detail. We searched the PubMed and Medline databases and identified 53 publications with 221 patients reporting nuclear imaging findings in TTS. The age of the patients ranged from 17 to 87 years and were predominantly women (88.2%). The TTS variant was apical (typical) in 170 (76.9%), mid-ventricular in 23 (10.4%), and basal (reverse TTS) in 2 (0.9%). Cardiac perfusion was assessed using 99mTc sestamibi (MIBI) SPECT, 99mTc tetrofosmin SPECT, 201Tl SPECT, 82Rb PET, 201Tl SPECT, and 13N ammonia PET. Additional studies used were 123I MIBG SPECT, 123I BMIPP SPECT, 18F FDG PET, 67Ga citrate, and 11C hydroxy-ephedrine. A perfusion defect was seen in 69 (31.2%), and an inverse perfusion–metabolism mismatch (normal or near-normal perfusion with absent myocardial metabolic activity) was seen in 183 (82.8%) patients. Nuclear imaging has a significant role in evaluating, diagnosing, and prognosticating patients with TTS. As nuclear imaging technology evolves, we will surely gain more insights into this fascinating disorder.