SARS-CoV-2: Reinfection after 18 Months of a Previous Case with Multiple Negative Nasopharyngeal Swab Tests and Positive Fecal Molecular Test (original) (raw)

Detection of SARS-CoV-2 pneumonia: two case reports

Journal of Medical Case Reports

Background Developing therapeutic strategies for a SARS-CoV-2 infection is challenging, but first the correct diagnosis has to be made. Unspecific upper and lower respiratory tract symptoms can be misleading; hence, a nasopharyngeal swab test with a real-time reverse-transcription-polymerase chain reaction is of great importance. However, early viral clearing jeopardizes a sound diagnosis of COVID-19. Case presentation We report on two Caucasian patients who had negative pharyngeal swab tests at the onset of SARS-CoV-2 pneumonia. In one patient, the virus was not even detectable in bronchoalveolar lavage despite typical radiomorphologic changes. Conclusions Negative PCR findings in both the pharynx and bronchoalveolar lavage do not exclude COVID-19 pneumonia. Computed tomography is a crucial diagnostic prerequisite in this context.

A 63-Year-Old Man with a Diagnosis of Re-Infection with SARS-CoV-2 Nine Weeks After an Initial Hospital Admission with COVID-19 Pneumonia

The American Journal of Case Reports, 2022

Patient: Male, 63-year-old Final Diagnosis: SARS-COV-2 reinfection Symptoms: Auscultatory changes typical for pneumonia • fever of 39°C • general weakness Medication: — Clinical Procedure: — Specialty: Diagnostics, Laboratory • Pulmonology Objective: Unusual clinical course Background: This report describes a 63-year-old Polish man presenting with COVID-19 (Coronavirus Disease 2019) pneumonia in early 2020, before vaccines to prevent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection were available. Nine weeks following recovery from the initial infection, he tested positive again for SARS-CoV-2. Case Report: Man, age 63, was admitted to the Military Institute of Medicine on March 12, 2020, with body temperature 40°C, a cough, and breathlessness. On March 12, 2020, SARS-CoV-2 RNA was found in a nasopharynx smear. A chest X-ray (RTG) showed discrete areas of interstitial densities. On June 13, 2020, after 32 days of hospitalization and 2 negative real-time polymer...

A Patient with Asymptomatic SARS-CoV-2 Infection Who Presented 86 Days Later with COVID-19 Pneumonia Possibly Due to Reinfection with SARS-CoV-2

American Journal of Case Reports, 2020

Unusual clinical course Background: Coronavirus disease 2019 (COVID-19) has radically changed the world, and promising vaccine trials are currently underway. The immune responses in asymptomatic and symptomatic individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are still under investigation, and data are evolving. While it is known that humoral and cell-mediated immune responses against SARS-CoV-2 are elicited, it is uncertain whether these responses protect against reinfection or that they provide definitive evidence of viral clearance. Very few cases have been reported in the literature regarding reinfection with SARS-CoV-2. Case Report: We present a case of a middle-aged man with asymptomatic SARS-CoV-2 infection who later developed mild symptomatic COVID-19 after a period of 3 months. The source of reinfection was likely from the community, which had a soaring burden of infection with the highest number of COVID-19 cases per million in the world at that time. The patient had 2 negative COVID-19 polymerase chain reaction (PCR) tests 2 weeks after the initial infection. During the second infection, a nasopharyngeal reverse-transcription PCR test and tests for the presence of COVID-19 immunoglobulin (Ig)M and IgG antibodies were all positive. Conclusions: Reinfection with SARS-CoV-2 is a strong possibility. This case raises concerns that asymptomatic infections may not provide long-term protective immunity to all patients, which could make them susceptible to reinfection. Possible explanations for reinfection include an interval decrease in protective antibodies titers after SARS-CoV-2 infection that may be more prevalent in patients who had an asymptomatic infection. Other possibilities include viral reactivation after a prolonged carriage of the virus or delayed immune response.

RT- PCR testing of upper respiratory tract samples for diagnosis of SARS-CoV-2: Between justification and overestimation, a multi-center international study

Travel Medicine and Infectious Disease

Background: It has been found that patients recovered from COVID 19 may still test Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) positive without being infectious; the reasons are unclear. The occurrence of false-negative results of RT-PCR interferes with a proper diagnosis. The objectives of that work were to determine factors associated with persistently detectable SARS-CoV-2 RNA among recovered hospitalized patients and to determine the incidence of false-negative RT-PCR results and associated factors. Methods: Relevant data were collected from 482 COVID 19 patients hospitalized in six referral centers from four countries. Results: The median duration of RT-PCR conversion to negative was 20 days. Out of 482 studied patients, 8.7% tested positive after more than four weeks and were considered prolonged convertors. Binary logistic regression analysis revealed headache as an independent risk factor for short conversion time while fever, hypertension, chronic obstructive pulmonary disease, lymphopenia, elevated erythrocyte sedimentation rate, and the number of lobes affected, and bilateralism were found to be independent risk factors for prolonged positivity. Eighteen patients had initial negative results then turned positive after 24-48 h. Associated factors and outcomes were identified. Conclusion: Identifying patients with a high likelihood of COVID-19 despite a negative RT-PCR is critical for effective clinical care. However, patient isolation resumption depending on positive RT-PCR despite clinical and radiological recovery is an overrating that greatly burdens the health sector.

Evaluation of FAST COVID-19 SARS-CoV-2 Antigen Rapid Test Kit for Detection of SARS-CoV-2 in Respiratory Samples from Mildly Symptomatic or Asymptomatic Patients

Diagnostics, 2022

Molecular tests are the gold standard to diagnose severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection but are associated with a diagnostic delay, while antigen detection tests can generate results within 20 min even outside a laboratory. In order to evaluate the accuracy and reliability of the FAST COVID-19 SARS-CoV-2 Antigen Rapid Test Kit (Ag-RDT), two respiratory swabs were collected simultaneously from 501 patients, with mild or no coronavirus disease 2019 (COVID-19)-related symptoms, and analyzed with both the Reverse Transcriptase-quantitative Polymerase Chain Reaction (RT-qPCR) and the FAST COVID-19 SARS-CoV-2 Antigen Rapid Test. Results were then compared to determine clinical performance in a screening setting. We measured a precision of 97.41% (95% CI 92.42–99.15%) and a recall of 98.26% (95% CI 93.88–99.25%), with a specificity of 99.22% (95% CI 97.74–99.74%), a negative predictive value of 99.48% (95% CI 97.98–99.87%), and an overall accuracy of 99.00%...

Detection and quantification of SARS-CoV-2 by droplet digital PCR in real-time PCR negative nasopharyngeal swabs from suspected COVID-19 patients

PLOS ONE, 2020

Since SARS-CoV-2-based disease (COVID-19) spreads as a pandemic, the necessity of a highly sensitive molecular diagnosis that can drastically reduce false negatives reverse transcription PCR (rtPCR) results, raises as a major clinical need. Here we evaluated the performance of a ddPCR-based assay to quantify SARS-CoV-2 titer in 55 suspected COVID-19 cases with negative rtPCR results thanks to in-house ddPCR assay (targeting RdRp and host RNaseP). Samples were collected at ASST-GOM Niguarda between February and May 2020 at hospital admission. Clinical and imaging data were obtained for clinical staging and definition of disease severity. Patients were mainly female (45.5%) with a median age of 73 (57-84) years. ddPCR-based assay detected SARS-CoV-2 genome in nasopharyngeal samples of 19 (34.5%) patients (median viral-load: 128 copies/mL, IQR: 72-345). In 15 of them (78.9%), chest CT showed a classical COVID-19 bilateral interstitial pneumonia; 14 patients (73.7%) showed severe COVID-19 manifestations. ddPCR did not identify any trace of SARS-CoV-2 genome in the respiratory samples of the remaining 36 patients. The serological assay performed in a subgroup of 34 patients at the later stage of illness (from 3 days to 90 days after) confirmed the presence of SARS-CoV-2 antibodies in all patients tested positive for SARS-CoV-2 in ddPCR (100%). Contrariwise, negative tests were observed in 95.0% ddPCR negative patients (P<0.001). Thanks to a ddPCR-based assay, we achieved a rapid and accurate SARS-CoV-2 diagnosis in rtPCR-negative respiratory

Temporal Change of SARS-CoV-2 in Clinical Specimens of COVID-19 Pneumonia Patients

The American Journal of Tropical Medicine and Hygiene, 2020

The quality and type of specimen collection affect the sensitivity of real-time reverse transcriptase-PCR (rRT-PCR) for the diagnosis of SARS-CoV-2. In this report, the course over time of rRT-PCR for SARS-CoV-2 in 26 clinical specimens collected from the upper (nasopharyngeal and throat swabs) and lower (sputum) respiratory tracts of COVID-19 cases with pneumonia was investigated along with the clinical course. The preliminary results revealed that higher SARS-CoV-2 RNA concentration and longer time for detection make self-collected sputum a preferable specimen for the diagnosis and follow-up of COVID-19 pneumonia. Self-collection of sputum can minimize the risk of unnecessary exposure to healthcare workers, preserve the shortage of personal protective equipment, and limit viral transmission to the environment.

Radiological Findings Increased the Successful of COVID-19 Diagnosis in Hospitalized Patients Suspected of Respiratory Viral Infection but with a Negative First SARS-CoV-2 RT-PCR Result

Diagnostics, 2022

SARS-CoV-2 is the etiological agent of COVID-19 and may evolve from asymptomatic disease to fatal outcomes. Real-time reverse-transcription polymerase chain reaction (RT-PCR) screening is the gold standard to diagnose severe accurate respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, but this test is not 100% accurate, as false negatives can occur. We aimed to evaluate the potential false-negative results in hospitalized patients suspected of viral respiratory disease but with a negative previous SARS-CoV-2 RT-PCR and analyze variables that may increase the success of COVID-19 diagnosis in this group of patients. A total of 55 hospitalized patients suspected of viral respiratory disease but with a previous negative RT-PCR result for SARS-CoV-2 were included. All the participants had clinical findings related to COVID-19 and underwent a second SARS-CoV-2 RT-PCR. Chest-computed axial tomography (CT) was used as an auxiliary tool for COVID-19 diagnosis. After the second test, 3...