Colombia
| Artículo de revista
Comments to: A systematic review of pathological findings in COVID-19: a pathophysiological timeline and possible mechanisms of disease progression
Fecha
2020-07Registro en:
0893-3952
1530-0285
Autor
Parra Medina, Rafael
Herrera, Sabrina
Mejía, Jaime
Resumen
We reviewed the excellent systematic article published by
Pola et al. [1] about the pathological findings in COVID-19.
Based on the 250 COVID-19 autopsies found during our
systematic review through March 30, 2020; we concur with
the article hypothesis of mechanisms of infection and the
tissular injury. However, we would like to highlight two
topics that the authors did not discuss.
The first, the autopsies findings could support the
hypothesis of macrophages hyperactivation. This has already
been reported in other coronavirus such as SARS-CoV1 and
MERS [2]. In the initial autopsies in COVID-19 patients, the
presence of CD68+ macrophages in lung and heart tissues
[3, 4] and the presence of CD169+ macrophages in lymph
node subcapsular spaces and in splenic marginal zone were
reported. These macrophages expressed the SARS-CoV-2
entry receptor ACE2 and contained SARS-CoV-2 nucleoprotein [5]. Disorders of macrophages as secondary hemophagocytic lymphohistiocytosis (sHLH) have been reported
in COVID-19 . In autopsies, hemophagocytosis has
been observed in lung, lymph node, bone marrow, liver, and
spleen . sHLH is a hyperinflammatory syndrome
characterized by a fulminant and fatal hypercytokinaemia
with multiorgan failure. In adults, sHLH is mostly triggeredby viral infections, autoimmune diseases and neoplasms
[11], and occurs in 3.7–4.3% of sepsis cases [12]. The
diagnosis of sHLH is based on clinical, laboratory, and
morphologic criteria. The main features are: unremitting
fever, cytopenias, hepatosplenomegaly, hypertriglyceridemia, hypofibrinogenemia, and hyperferritinemia.
Severe COVID-19 could be considered a hyperferritinemic
syndrome by the clinical similarities detected . In these
conditions, Ferritin plays a critical role in the immune
response. The production and secretion of extracellular ferritin is derived from macrophages.