Published online Sep 9, 2023. doi: 10.5492/wjccm.v12.i4.226
Peer-review started: May 11, 2023
First decision: June 15, 2023
Revised: June 24, 2023
Accepted: July 6, 2023
Article in press: July 6, 2023
Published online: September 9, 2023
During the second wave of the coronavirus disease 2019 (COVID-19) pandemic, a subset of critically ill patients developed delayed respiratory deterioration in the absence of new infection, fluid overload or extra-pulmonary organ dysfunction.
To describe the clinical and laboratory characteristics, outcomes, and management of these patients, and to contrast this entity with other post COVID-19 immune dysregulation related inflammatory disorders.
This was a retrospective observational study of adult patients admitted to the medical intensive care unit of a 2200-bed university affiliated teaching hospital, between May and August 2021, who fulfilled clearly defined inclusion and exclusion criteria. Outcome was assessed by a change in PaO2/FiO2 ratio and levels of inflammatory markers before and after immunomodulation, duration of mechanical ventilation after starting treatment, and survival to discharge.
Five patients developed delayed respiratory deterioration in the absence of new infection, fluid overload or extra-pulmonary organ dysfunction at a median interquartile range (IQR) duration of 32 (23-35) d after the onset of symptoms. These patients had elevated inflammatory markers, required mechanical ventilation for 13 (IQR 10-23) d, and responded to glucocorticoids and/or intravenous immunoglobulin. One patient died (20%).
This delayed respiratory worsening with elevated inflammatory markers and clinical response to immunomodulation appears to contrast the well described Multisystem Inflammatory Syndrome – Adults by the paucity of extrapulmonary organ involvement. The diagnosis can be considered in patients presenting with delayed respiratory worsening, that is not attributable to cardiac dysfunction, fluid overload or ongoing infections, and associated with an increase in systemic inflammatory markers like C-reactive protein, inteleukin-6 and ferritin. A good response to immunomodulation can be expected. This delayed inflammatory pulmonary syndrome may represent a distinct clinical entity in the spectrum of inflammatory syndromes in COVID-19 infection.
Core Tip: Delayed respiratory deterioration in critically ill coronavirus disease 2019 (COVID-19) in the absence of new infection, fluid overload, pneumothorax, or lung collapse is seen in a subset of patients admitted to the intensive care unit. This presentation does not fit in to the definition of Multisystem Inflammatory Syndrome Adults, owing to the predominance of pulmonary symptoms and the notable absence of cardiac, gastrointestinal, and mucocutaneous manifestations. In the current study, five patients developed worsening respiratory function requiring escalation of ventilatory support after the third week of COVID-19 illness. This was accompanied by elevated inflammatory markers. All five patients showed clinical response to immunomodulation. This delayed inflammatory pulmonary syndrome contrasts Multisystem Inflammatory Syndrome Adults where extrapulmonary organ involvement predominates.