Discussion
The possibility of SARS-CoV-2 co-infections with bacterial, fungal and
also viral pathogens should not be neglected. Fungal co-infections among
hospitalized patients with COVID-19 is a challenging issue. Few recent
studies revealed cases of COVID-19 infection involving more than one
species of aspergillus or concomitant two different fungal infections.
Costache et al. reported a case of COVID-19 associated pulmonary
aspergillosis with both Aspergillus fumigatus andAspergillus flavus with favorable outcome [2]. Johnson et al.
reported a case of combined probable pulmonary aspergillosis and
possible mucormycosis in a diabetic male with COVID-19 in the ICU who
treated with liposomal amphotericin B [3].
Critical illness is an important risk factor for CMV reactivation due to
immunosuppression. Although co-infections with CMV are frequent in the
critically ill patients, but the impact on COVID-19 patients is unclear.
Moniz et al. presented five case reports of CMV reactivation in COVID-19
patients admitted to the ICU with respiratory failure [4]. It has
been well described that critical or severe illness can induce immune
suppression. The most common laboratory finding in patients with
COVID-19 is lymphopenia, which correlate to diseases severity. Recent
findings revealed that disease severity is dominated by the decline in
cell-mediated immunity especially the decrease in T cell counts [5].
On the other hand, number of iatrogenic factors including the usage of
corticosteroids in the treatment of severe COVID-19 may predispose the
patients to other infection [6]. In addition to ICU admission and
mechanical ventilation, other entities including transfusions, sepsis,
corticosteroids and acute respiratory distress syndrome have also been
found to be associated with the risk of CMV reactivation [7].
In a minority of patients, bacterial and fungal co-infections can
complicate the course of COVID-19 infection. In a retrospective study,
the second most common respiratory pathogen detected from patients with
COVID-19 was Klebsiella pneumoniae [8, 9]. Montrucchio et al.
reported patients with COVID-19 related acute respiratory distress
syndrome who developed invasive infections due to
carbapenemase-producing Klebsiella pneumoniae [10]. In our patient,
the culture of empyema and visceral pleural peel, confirmed the
superimposed of Klebsiella pneumoniae infection on COVID-19.
Tissue invasion by a filamentous fungus through histopathological
examination of biopsy, provides a diagnosis of proven invasive fungal
infections and positive culture of Aspergillus from the specimen
is required to make a proven diagnosis of invasive aspergillosis
[11]. In our case, right upper lobe wedge resection and right lower
lobe wedge resection revealed wide and irregular fungal hyphae
indicative of mucormycosis. Also vessel wall infiltrated by several thin
and also broad fungal hyphae. Calcium oxalate crystals accompanied by
fungal hyphae was indicative of aspergillosis. Definitive diagnosis of
CMV pneumonia is determined based on lung tissue samples by
histopathologic testing and immunohistochemical analysis [12].
According to the data, our case is consistent with the proven CMV
pneumonia.
According to the histopathology and IHC, our patient had pulmonary
aspergillosis, mucormycosis, and CMV disease with Klebsiella
pneumoniae infection. The combined risk factors including diabetes
mellitus, recent corticosteroid treatment and also COVID-19 per se,
contributed to concomitant infections in our patient which is a unique
report.