Discussion:
Up to now, there are limited data about the impact of COVID-19 on
mucormycosis or other fungal infections. On the one hand, the robust
inflammatory immune response following COVID-19 and usage of
immunosuppressive drugs afterwards, provides a favorable condition for
development of fungal co-infections. On the other hand, it is suggested
that venous thromboembolism (VTE) caused by COVID-19 infection leads to
mechanical ventilation, central venous catheterization, and surgeries,
all of which could damage elastic lamina of blood vessels and eventually
trigger the propagation of mucorales (3). Furthermore, comorbidities
such as diabetes mellitus and diabetic nephropathy are risk factors for
both COVID-19 and mucormycosis (8).
This case report is consistent with other case reports in which diabetes
mellitus was a predisposing condition regarding SARS-CoV-2 and
mucormycosis co-infection. Besides, this case had multiple underlying
health conditions including diabetic ketoacidosis, diabetic nephropathy,
hypertension and history of CABG surgery. All of these conditions,
increase COVID-19 severity and the risk of co-infection or
superinfection with other microorganisms (9). Unfortunately, this case
had a poor prognosis due to extensive involvement of rhino-orbital
mucormycosis and ARDS and passed away after one month of
hospitalization.
Based on a broad literature search, the presented case had some unique
features compared to the similar reported cases. First of all, Diabetic
nephropathy followed by hemodialysis has not been reported in concurrent
infection of COVID-19 and mucormycosis. Secondly, limited cases of
diabetic ketoacidosis as a comorbidity in SARS-CoV-2 co-infected with
mucormycosis have been reported previously (10, 11). The presented case
was the only case with uncontrolled diabetes mellitus, diabetic
ketoacidosis, diabetic nephropathy under hemodialysis and hypertension
who was suffering from rhino-orbital mucormycosis following severe
COVID-19 infection. It should be noted that in reports from different
countries other underlying health conditions have also been associated
with mucormycosis following COVID-19 such as; Hematological
malignancies, Hypothyroidism, Asthma and obesity with median age of 53.4
and male sex comprising the majority of the cases (12-19).
Up to July 4, four cases of rhino-orbital–cerebral mucormycosis
following COVID-19 have been reported in Iran. The median age of the
patients was 51.2 years. Besides, 3 out of 4 were women. Diabetes
mellitus was the most historical condition (3 of 4). Of these four
cases, one death was reported. Amphotericin B was prescribed for all of
them as the first line treatment for mucormycosis infection(20-22).
Mucormycosis is a serious opportunistic fungal infection that could lead
to rhino-orbital, gastrointestinal, pulmonary, renal, cutaneous and
disseminated infections. The infection enters the host via respiratory
tract. Since it has a noticeable affinity for arteries it grows in
internal elastic lamina, which triggers thrombosis and infarction (23).
The disease can progress from nose and sinuses directly or through
vascular occlusion. Invasion through superior orbital fissure,
ophthalmic vessels, cribriform plate, carotid artery or possibly via a
perineural route can involve intracranial part (24).
Necrotic tissue surgical debridement, treatment with liposomal
amphotericin B as an antifungal therapy and risk factors control were
suggested to improve survival (25).
Since COVID-19 pandemic is continuing in Iran and mass vaccination has
not been started yet, co-infection of SARS-CoV-2 and other
microorganisms should be taken under consideration. Prescribing
immuno-suppressants for COVID-19 patients with underlying health
conditions should be done more cautiously along with continuous
monitoring. In spite of massive researches on COVID-19 management
performing all around the world, extensive researches are needed
regarding better prevention and management of opportunistic infections
among COVID-19 patients, yet.