Atypical bacterial co‐infections among patients with COVID‐19: A study from India

Abstract

Emerging evidence shows co-infection with atypical bacteria in coronavirus disease 2019 patients. Respiratory illness caused by atypical bacteria such as Mycoplasma pneumoniae, Chlamydia pneumoniae, and Legionella pneumophila may show overlapping manifestations and imaging features with COVID-19 causing clinical and laboratory diagnostic issues. We conducted a prospective study to identify co-infections with SARS-CoV-2 and atypical bacteria in an Indian tertiary hospital. From June 2020 to January 2021, a total of 194 patients with laboratoryconfirmed COVID-19 were also tested for atypical bacterial pathogens. For diagnosing M. pneumoniae, a real-time polymerase chain reaction (PCR) assay and serology (IgM ELISA) were performed. C. pneumoniae diagnosis was made based on IgM serology. L. pneumophila diagnosis was based on PCR or urinary antigen testing. Clinical and epidemiological features of SARS-CoV-2 and atypical bacteria-positive and -negative patient groups were compared. Of the 194 patients admitted with COVID-19, 17 (8.8%) were also diagnosed with M. pneumoniae (n = 10) or C. pneumoniae infection (n = 7). Confusion, headache, and bilateral infiltrate were found more frequently in the SARS CoV-2 and atypical bacteria co-infection group. Patients in the M. pneumoniae or C. pneumoniae co-infection group were more likely to develop ARDS, required ventilatory support, had a longer hospital length of stay, and higher fatality rate compared to patients with only SARS-CoV-2. Our report highlights co-infection with bacteria causing atypical pneumonia should be considered in patients with SARS-CoV-2 depending on the clinical context. Timely identification of co-existing pathogens can provide pathogen-targeted treatment and prevent fatal outcomes of patients infected with SARS-CoV-2 during the current pandemic.

SARS-CoV-2–Legionella Co-Infections: A Systematic Review and Meta-Analysis (2020–2021)

“…After applying the inclusion and exclusion criteria ( Figure 1 ), a total of 38 articles were included in the qualitative synthesis [ 23 , 24 , 26 , 28 , 29 , 35 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 ]. More precisely, 27 observational studies (see Table 1 for details), 1 case series, and 10 case reports (see Appendix A for details) were included.…”

“…The corresponding share of sampled patients ranged from 2.1% [ 59 ] to 100% [ 27 , 42 , 43 , 45 , 48 , 51 , 53 , 58 , 62 , 63 ] of index cases. In most cases, their status was assessed with Urinary Legionella Antigen Testing (ULAT) (76.7%), but a substantial share of them was also assessed with PCR on bronchial specimens (23.3%).…”

“…Overall, 18 cases of co-infections were retrieved (0.4% of total samples), with the majority of studies (18 out of 27, 66.7%) not reporting a single occurrence [ 23 , 24 , 26 , 42 , 44 , 46 , 48 , 50 , 53 , 54 , 55 , 56 , 58 , 59 , 61 , 63 ]. The majority of diagnoses was obtained from studies performed during the “first wave” (61.1%) and in European countries (50.0%).…”

“…; Pseudomonas spp. ; Staphilococci , and Enterococci) that may peak at up to 20% of incident cases, the potential occurrence of Legionella infections may therefore appear quite insignificant [ 42 , 43 , 74 ], and substantially lower than that addressed by early reports from mainland China [ 27 ]. Moreover, it should be stressed that nearly half of the sampled cases were from ICUs (i.e., 47.4%), an estimate that exceeds most of the available reports for SARS-CoV-2 infections, even for the “first wave,” [ 75 , 76 ], when Grasselli et al reported a utilization of ICU equal to 16% of all hospitalizations [ 76 ].…”

“…The majority of the reports came from European countries (n = 17, 63.0%), followed by China (n = 4, 14.8%) and India (n = 2, 7.4%), while a single report was retrieved from Israel, Japan, Peru, and the USA, respectively (3.7% each). Overall, 18 cases of co-infections were retrieved (0.4% of total samples), with the majority of studies (18 out of 27, 66.7%) not reporting a single occurrence [23,24,26,42,44,46,48,50,[53][54][55][56]58,59,61,63]. The majority of diagnoses was obtained from studies performed during the "first wave" (61.1%) and in European countries (50.0%).…”