Type-H, and Type-L COVID-19: are they different subtypes or the same?

SARS-CoV-2 infection, which causes severe pneumonia, caused an epidemic that started in Wuhan, China in December 2019 and spread to the whole world. COVID-19 mainly affects the respiratory system and causes the development of severe pneumonia and related acute respiratory distress syndrome (ARDS) in some patients. We aimed to investigate whether COVID-19 pneumonia cases can be evaluated in different categories in clinical and radiological terms.

COVID-19 associated ARDS cases being treated with the diagnosis of severe pneumonia between March 21, 2020 and June 15, 2020 in Anesthesia Intensive Care Unit were examined and divided into 2 groups (type-L and type-H, total 29 cases) according to their clinical findings (according to whether they benefited from high PEEP and their lung compliance) and lung computed tomography findings (according to the severity of the ground glass appearance). The groups were compared with each other in terms of inflammatory markers [CRP (C reactive protein), ferritin, D Dimer, PCT (procalcitonin), white blood cell, lymphocyte count, arterial blood gas analysis] and imaging findings.

It was observed that the prone position was beneficial in improving oxygenation in both H-type and L-type patients. 7 of 22 L-type patients were intubated and 5 of these patients died. There was no statistical difference between the two groups in terms of intubation times, hospital stays, cytokine levels, prone position application responses and mortality rates.

Are there two separate forms of COVID-19 pneumonia, such as h-type and l-type, or are they intertwined and describe the early and late stages of the disease? This question needs to be discussed. In addition, we believe that subtyping COVID-19 pneumonia patients does not make a difference in the treatments to be applied.