Neurological Complications in Children Hospitalized With Seizures and Respiratory Infections: A Comparison Between SARS-CoV-2 and Other Respiratory Infections

BACKGROUND

Children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can experience neurological symptoms, but limited data are available on neurological symptoms associated with other respiratory infections. We compared proportions of neurological symptoms in children hospitalized with seizures and respiratory infections, including SARS-CoV-2, influenza, and endemic coronaviruses.

METHODS

A retrospective cohort study was performed on children admitted for seizures who had positive respiratory polymerase chain reactions for SARS-CoV-2, coronavirus NL63, coronavirus OC34, influenza (A and B), adenovirus, Mycoplasma pneumoniae, or parainfluenza 3 or 4. Primary outcomes were rates of new neurological diagnoses and mortality.

RESULTS

A total of 883 children were included. Mortality rates ranged from 0% with M. pneumoniae to 4.9% with parainfluenza 4. Strokes were observed with all infections except for coronavirus OC43 and M. pneumoniae, with the highest rates in parainfluenza 4 (4.9%) and SARS-CoV-2 (5.9%). Compared with other infections, children with SARS-CoV-2 were older, had higher rates of stroke, and lower rates of intubation. The most common brain magnetic resonance imaging (MRI) abnormality was diffusion restriction. Abnormal MRI rates were lower in SARS-CoV-2, compared with patients with other coronavirus (OC). However, rates of stroke, encephalopathy, hypoxic-ischemic encephalopathy, and meningoencephalitis were similar between SARS-CoV-2 and influenza cohorts.

CONCLUSIONS

In children hospitalized with seizures, higher rates of stroke were observed in SARS-CoV-2 versus OC. Similar rates of neurological symptoms were observed in patients with SARS-CoV-2 and those with influenza. Strokes can occur in children with these viral infections, particularly SARS-CoV-2.

Universal use of surgical masks is tolerated and prevents respiratory viral infection in stem cell transplant recipients

Prevention of respiratory viral infection in stem cell transplant patients is important due to its high risk of adverse outcome. This single-centre, mixed methods study, conducted before the severe acute respiratory syndrome coronavirus-2 pandemic, explored the barriers and facilitators to a policy of universal mask use by visitors and healthcare workers, and examined the impact of the first year of introduction of the policy on respiratory viral infection rates compared with preceding years, adjusted for overall incidence. Education around universal mask use was highlighted as being particularly important in policy implementation. A significant decrease in respiratory viral infection was observed following introduction.

Pathogenesis of a novel porcine parainfluenza virus type 1 isolate in conventional and colostrum deprived/caesarean derived pigs

Two experimental challenge studies were conducted to evaluate the pathogenesis of a porcine parainfluenza virus type 1 (PPIV-1) isolate. Four-week-old conventional (CON) pigs were challenged in Study 1 and six-week-old caesarean derived/colostrum deprived (CDCD) pigs were challenged in Study 2. Results indicate that PPIV-1 shedding and replication occur in the upper and lower respiratory tracts of CON and CDCD pigs as detected by RT-qPCR and immunohistochemistry. Mild macroscopic lung lesions were observed in CON pigs but not in CDCD pigs. Microscopic lung lesions were mild and consisted of peribronchiolar lymphocytic cuffing and epithelial proliferation in CON and CDCD pigs. Serum neutralizing antibodies were detected in the CON and CDCD pigs by 14 and 7 days post inoculation, respectively. This study provides evidence that in spite of PPIV-1 infection and replication in challenged swine, significant clinical respiratory disease was not observed.

Protective antibodies against human parainfluenza virus type 3 infection

Human parainfluenza virus type III (HPIV3) is a common respiratory pathogen that afflicts children and can be fatal in vulnerable populations, including the immunocompromised. There are currently no effective vaccines or therapeutics available, resulting in tens of thousands of hospitalizations per year. In an effort to discover a protective antibody against HPIV3, we screened the B cell repertoires from peripheral blood, tonsils, and spleen from healthy children and adults. These analyses yielded five monoclonal antibodies that potently neutralized HPIV3 in vitro. These HPIV3-neutralizing antibodies targeted two non-overlapping epitopes of the HPIV3 F protein, with most targeting the apex. Prophylactic administration of one of these antibodies, PI3-E12, resulted in potent protection against HPIV3 infection in cotton rats. Additionally, PI3-E12 could also be used therapeutically to suppress HPIV3 in immunocompromised animals. These results demonstrate the potential clinical utility of PI3-E12 for the prevention or treatment of HPIV3 in both immunocompetent and immunocompromised individuals.

The traditional use of southern African medicinal plants in the treatment of viral respiratory diseases: A review of the ethnobotany and scientific evaluations

ETHNOPHARMACOLOGICAL RELEVANCE

Viral respiratory infections are amongst the most common infections globally, with most of the world's population contracting at least one infection annually. Numerous plant species are used in traditional southern African healing systems to treat these diseases and to alleviate the symptoms. Despite this, the therapeutic potential of these plants against viral respiratory diseases remains poorly explored.

AIM OF THE STUDY

The aim of this study was to document the southern African plant species used in traditional medicine to treat viral respiratory infections. We also examined the extent of scientific evaluations of southern African plant species against the respiratory-infective viruses, with the aim of stimulating interest in this area and focusing on future studies.

MATERIALS AND METHODS

We undertook an extensive review of ethnobotanical books, reviews and primary scientific studies to identify southern African plants which are used in traditional southern African medicine to treat viral respiratory diseases. This information was used to identify gaps in the current research that require further study.

RESULTS

Two hundred and fifty-seven southern African plant species were identified as traditional therapies for viral respiratory diseases. Surprisingly, only one of those species (as well as twenty-one other species not recorded for these purposes) has been evaluated for the ability to block respiratory virus production. Furthermore, most of these studies screened against a single viral strain and none of those studies examined the mechanism of action of the plant preparations.

CONCLUSIONS

Despite well documented records of the use of southern African plants to treat respiratory viral diseases, the field is poorly explored. Nearly all of the plant species used in traditional healing systems to treat these diseases are yet to be tested. Substantial further work is required to verify the efficacy of these traditional medicines.

Respiratory Virus Infections of the Stem Cell Transplant Recipient and the Hematologic Malignancy Patient

Respiratory virus infections in hematologic stem cell transplant recipients and patients with hematologic malignancies are increasingly recognized as a cause of significant morbidity and mortality. The often overlapping clinical presentation makes molecular diagnostic strategies imperative for rapid diagnosis and to inform understanding of the changing epidemiology of each of the respiratory viruses. Most respiratory virus infections are managed with supportive therapy, although there is effective antiviral therapy for influenza. The primary focus should remain on primary prevention infection control procedures and isolation precautions, avoidance of ill contacts, and vaccination for influenza.

Prevalence of Human Parainfluenza Viruses and Noroviruses Genomes on Office Fomites

The aim of this study was to evaluate the potential role of office fomites in respiratory (human parainfluenza virus 1-HPIV1, human parainfluenza virus 3-HPIV3) and enteric (norovirus GI-NoV GI, norovirus GII-NoV GII) viruses transmission by assessing the occurrence of these viruses on surfaces in office buildings. Between 2016 and 2017, a total of 130 surfaces from open-space and non-open-space rooms in office buildings located in one city were evaluated for HPIV1, HPIV3, NoV GI, and NoV GII viral RNA presence. Detection of viruses was performed by RT-qPCR method. Study revealed 27 positive samples, among them 59.3% were HPIV3-positive, 25.9% HPIV1-positive, and 14.8% NoV GII-positive. All tested surfaces were NoV GI-negative. Statistical analysis of obtained data showed that the surfaces of office equipment including computer keyboards and mice, telephones, and desktops were significantly more contaminated with respiratory viruses than the surfaces of building equipment elements such as door handles, light switches, or ventilation tracts (χ 2 p = 0.006; Fisher's Exact p = 0.004). All examined surfaces were significantly more contaminated with HPIVs than NoVs (χ 2 p = 0.002; Fisher's Exact p = 0.003). Office fomites in open-space rooms were more often contaminated with HPIVs than with NoVs (χ 2 p = 0.016; Fisher's Exact p = 0.013). The highest average concentration of HPIVs RNA copies was observed on telephones (1.66 × 102 copies/100 cm2), while NoVs on the light switches (1.40 × 102 copies/100 cm2). However, the Kruskal-Wallis test did not show statistically significant differences in concentration levels of viral RNA copies on surfaces between the all tested samples. This study unequivocally showed that individuals in office environment may have contact with both respiratory and enteric viral particles present on frequently touched surfaces.

Rescue of Sendai Virus from Cloned cDNA

Sendai virus (SeV) is a non-segment negative-sense RNA virus that naturally infects and causes pneumonia in mice. As a prototypic member of the family Paramyxoviridae, SeV has been characterized well, and these studies revealed numerous traits of paramyxovirus biology. The reverse genetics system to rescue SeV was first established in 1995. The virus was rescued from a cloned cDNA that contains full genome sequence flanked by T7 promoter and hepatitis delta virus ribozyme. To rescue SeV, it is necessary to infect cells with a recombinant vaccinia virus vTF7.3 that expresses T7 RNA polymerase, and transfect with the SeV full genome cDNAs together with supporting plasmids encoding NP, P, and L genes under the T7 promoter. Synthesized viral RNA by T7 RNA polymerase will be encapsidated with NP and associated with a polymerase complex composed of P and L. The polymerase complex transcribes and replicates the genome, and produces progeny virions. Rescued SeV needs to be plaque purified to exclude vTF7.3 from viral stock. Reverse genetics system of SeV is relatively efficient compared to other paramyxoviruses, but alternative approaches to rescue poorly growing mutant viruses are also available.

In vitro sensitivity of human parainfluenza 3 clinical isolates to ribavirin, favipiravir and zanamivir

BACKGROUND

Human parainfluenza type 3 (HPIV3) is an important respiratory pathogen. Although a number of potential therapeutic candidates exist, there is currently no licensed therapy or vaccine. Ribavirin (RBV), favipiravir (FVP) and zanamivir (ZNV) are inhibitors with proven activity against influenza and with potential inhibitory activity against HPIV3 laboratory adapted strains in vitro.

OBJECTIVES

To evaluate RBV, FVP and ZNV as inhibitors of minimally passaged UK clinical strains of HPIV3 as well as a laboratory adapted strain MK9 in vitro.

STUDY DESIGN

The inhibitory action of RBV, FVP and ZNV was evaluated against nine minimally passaged clinical strains and a laboratory adapted strain MK9 using plaque reduction and growth curve inhibition in a cell culture model.

RESULTS

Clinical isolates were found to be at least as susceptible as the laboratory adapted strains to RBV and FVP and significantly more susceptible to ZNV. However the inhibitory concentrations achieved by ZNV against clinical strains remain prohibitively high in vivo.

CONCLUSIONS

RBV, FVP and ZNV were found to be effective inhibitors of HPIV3 in vitro. The lack of efficacy of RBV in vivo may be due to inability to reach required therapeutic levels. FVP, on the other hand, is a good potential therapeutic agent against HPIV3. Further studies using wild type clinical strains, as well as better formulation and delivery mechanisms may improve the utility of these three inhibitors.

Surveillance, isolation and complete genome sequence of bovine parainfluenza virus type 3 in Egyptian cattle

Parainfluenza virus type 3 (PIV-3) can infect a wide variety of mammals including humans, domestic animals, and wild animals. In the present study, bovine parainfluenza virus type 3 (BPIV-3) was isolated from nasal swabs of Egyptian cattle presenting with clinical signs of mild pneumonia. The virus was isolated in Madin-Darby bovine kidney (MDBK) cells and confirmed by reverse transcription-polymerase chain reaction (RT-PCR). The complete genome of Egyptian BPIV-3 strain was sequenced by using next generation (Illumina) sequencing. The new isolate classified with genotype A of BPIV-3 and was closely related to the Chinese NM09 strain (JQ063064). Subsequently in 2015–16, a molecular surveillance study was undertaken by collecting and testing samples from cattle and buffaloes with respiratory tract infections. The survey revealed a higher rate of BPIV-3 infection in cattle than in buffaloes. The infection was inversely proportional to the age of the animals and to warm weather. This report should form a basis for further molecular studies on animal viruses in Egypt.

A parainfluenza virus type 3 outbreak at a residential aged care facility: The role of microbiologic testing in early identification and antimicrobial stewardship

We report an outbreak of parainfluenza 3, which had an attack rate of 30%, in a residential care facility in Melbourne, Australia. One-fifth of affected residents required hospitalization, but there were no deaths. The outbreak demonstrated the value of active surveillance and early microbiologic testing and the urgent need for antimicrobial stewardship programs in the aged care setting.

Vaccines in the Prevention of Viral Pneumonia

Pneumonia is of great global public health importance. Viral infections play both direct and indirect parts in its cause across the globe. Influenza is a leading cause of viral pneumonia in both children and adults, and respiratory syncytial virus is increasingly recognized as causing disease at both extremes of age. Vaccination offers the best prospect for prevention but current influenza vaccines do not provide universal and durable protection, and require yearly reformulation. In the future, it is hoped that influenza vaccines will give better and universal protection, and that new vaccines can be found for other causes of viral pneumonia.

Community acquired respiratory virus infections in cancer patients-Guideline on diagnosis and management by the Infectious Diseases Working Party of the German Society for haematology and Medical Oncology

Background

Community acquired viruses (CRVs) may cause severe disease in cancer patients. Thus, efforts should be made to diagnose CRV rapidly and manage CRV infections accordingly.

Methods

A panel of 18 clinicians from the Infectious Diseases Working Party of the German Society for Haematology and Medical Oncology have convened to assess the available literature and provide recommendations on the management of CRV infections including influenza, respiratory syncytial virus, parainfluenza virus, human metapneumovirus and adenovirus.

Results

CRV infections in cancer patients may lead to pneumonia in approximately 30% of the cases, with an associated mortality of around 25%. For diagnosis of a CRV infection, combined nasal/throat swabs or washes/aspirates give the best results and nucleic acid amplification based-techniques (NAT) should be used to detect the pathogen. Hand hygiene, contact isolation and face masks have been shown to be of benefit as general infection management. Causal treatment can be given for influenza, using a neuraminidase inhibitor, and respiratory syncytial virus, using ribavirin in addition to intravenous immunoglobulins. Ribavirin has also been used to treat parainfluenza virus and human metapneumovirus, but data are inconclusive in this setting. Cidofovir is used to treat adenovirus pneumonitis.

Conclusions

CRV infections may pose a vital threat to patients with underlying malignancy. This guideline provides information on diagnosis and treatment to improve the outcome.

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Community acquired viral respiratory tract infections can be life-threatening in cancer patients.

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Respiratory virus infections need early and appropriate management to improve outcome and avoid outbreaks.

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This guideline summarises recommendations by the AGIHO on community acquired respiratory viruses in cancer patients.

Use of laboratory and administrative data to understand the potential impact of human parainfluenza virus 4 on cases of bronchiolitis, croup, and pneumonia in Alberta, Canada

Background

Human Parainfluenza Virus (hPIV) causes severe respiratory illness in infants and adults. Our study describes the association of hPIV1–4 with bronchiolitis, croup, and pneumonia using retrospective laboratory, administrative and public health data. Due to issues including the historic lack of hPIV4 in some commercial respiratory virus panels, the description of the impact of hPIV4 on croup, bronchiolitis, and pneumonia at population levels has often been limited. This study will use routine clinical laboratory data, and administrative data to provide a preliminary description of the impact of hPIV4 on these diseases in our population.

Methods

A three year cohort of patients positive for hPIV was linked with data from physician visits and hospital admissions to define cases and hospitalization status. International Classification of Disease (ICD-9) codes were used to determine if cases had croup, bronchiolitis, and pneumonia. We also looked at differences in hospitalization status, age and gender among hPIV1–4. All statistical analysis was done using SPSS (Version 19.0.0, IBM Corp© 2010) and Graphpad Prism V6 (GraphPad Software, Inc., 2012).

Results

Only hPIV1 and hPIV4 specimens had positivity rates greater than 5 % of all specimens sent for respiratory virus panel testing. hPIV1 exhibited a biennial pattern while the pattern for hPIV3 was less interpretable due to lower positivity rates. Circulation patterns for hPIV2 and hPIV4 were not assessed due to the low positivity rates of theses specimens. From 2010 to 2013, there were 2300 hPIV cases with hPIV3 (46 %) being the most common, followed by hPIV1 (27 %), hPIV4 (16 %) and hPIV2 (11 %). The median age was 2 years for all hPIV types. Males were slightly greater than females for hPIV1 and hPIV2, with an equal distribution for hPIV3 and slightly more females than males for hPIV4. hPIV1 and hPIV2 had the highest or proportion of croup while hPIV3 and hPIV4 had the highest proportion of pneumonia. Within hPIV4 cases, distributions of diseases were; pneumonia (21 %, 95 % CI 17.1–25.7), bronchiolitis (18 %, 95 % CI 14.3–22.5), croup (2 %, 95 % CI 0.8–3.9), mixed illness of any of pneumonia, bronchiolitis or croup (4 %, 95 % CI 2.5–7.0) or other respiratory diseases (54 %, 95 % CI 49.1–59.6).

Conclusions

We used laboratory and administrative data to undertake a descriptive analysis of the association of hPIV1–4 with croup, bronchiolitis and pneumonia. hPIV4 appears to be more associated more with bronchiolitis and pneumonia and less with croup in our population.

Phase 1 clinical trials of DAS181, an inhaled sialidase, in healthy adults

DAS181, (study drug, Fludase®) was developed for treatment of influenza and parainfluenza infections. Delivered by inhalation, DAS181 cleaves sialic acid receptors from respiratory epithelial cells. Treatment of influenza for three days with DAS181 reduced viral shedding. To increase deposition in the upper airways and decrease systemic absorption, the particle size was increased to 10μm. We conducted two Phase I trials with three cohorts, randomized 2:1, active drug to placebo. The initial cohort got a single 20mg dose of DAS181, or placebo; the second, 20mg DAS181 or placebo for 10days, and the third got 20mg of DAS181 or placebo for 3days. Formulations differed slightly in their excipients. Subjects in the 1- and 3-day cohorts completed dosing without serious adverse events. Two subjects in the 10-day cohort stopped at Day 9 after developing respiratory and systemic symptoms, and a third experienced a decrease in FEV1 (Forced Expiratory Volume in 1s) after the 9th dose and a further decline after the 10th dose. Plasma DAS181, in the 10-day cohort, peaked and began falling before the last dose. Antibodies, predominately IgG with neutralizing activity, were detected in 15/18 subjects by Day 30. The highest IgG concentrations were in the 10-day cohort. The respiratory adverse events occurring after seven days and rapid drug clearance during continued dosing are consistent with the induction of DAS181 antibodies. This could preclude use of this medication for longer than seven days or for repeated courses. (These studies have been registered at ClinicalTrials.gov under registration Nos. NCT 00527865 and NCT 01651494.).

First report of severe parainfluenza virus 4B and rhinovirus C coinfection in a liver transplant recipient treated with immunoglobulin

We describe the first reported case of severe pneumonia due to coinfection by parainfluenza virus type 4B and rhinovirus C in a liver transplant recipient. The patient responded promptly to intravenous immunoglobulin and timely infection control measures prevented spreading of the infections. This report highlights respiratory viral coinfections as a possible cause of severe morbidity in transplant recipients and the importance of efficient molecular diagnostic technologies with major impact on clinical practice in a transplant center. It also describes a potential therapeutic strategy for such patients.

The neutralizing capacity of antibodies elicited by parainfluenza virus infection of African Green Monkeys is dependent on complement

The African Green Monkey (AGM) model was used to analyze the role of complement in neutralization of parainfluenza virus. Parainfluenza virus 5 (PIV5) and human parainfluenza virus type 2 were effectively neutralized in vitro by naïve AGM sera, but neutralizing capacity was lost by heat-inactivation. The mechanism of neutralization involved formation of massive aggregates, with no evidence of virion lysis. Following inoculation of the respiratory tract with a PIV5 vector expressing HIV gp160, AGM produced high levels of serum and tracheal antibodies against gp120 and the viral F and HN proteins. However, in the absence of complement these anti-PIV5 antibodies had very poor neutralizing capacity. Virions showed extensive deposition of IgG and C1q with post- but not pre-immune sera. These results highlight the importance of complement in the initial antibody response to parainfluenza viruses, with implications for understanding infant immune responses and design of vaccine strategies for these pediatric pathogens.

Rates of respiratory virus-associated hospitalization in children aged <5 years in rural northern India

OBJECTIVES

Though respiratory viruses are thought to cause substantial morbidity globally in children aged <5 years, the incidence of severe respiratory virus infections in children is unknown in India where 20% of the world's children live.

METHODS

During August 2009-July 2011, prospective population-based surveillance was conducted for hospitalizations of children aged <5 years in a rural community in Haryana State. Clinical data and respiratory specimens were collected. Swabs were tested by RT-PCR for influenza and parainfluenza viruses, respiratory syncytial virus (RSV), human metapneumovirus, coronaviruses, and adenovirus. Average annual hospitalization incidence was calculated using census data and adjusted for hospitalizations reported to occur at non-study hospitals according to a community healthcare utilization survey.

RESULTS

Of 245 hospitalized children, respiratory viruses were detected among 98 (40%), of whom 92 (94%) had fever or respiratory symptoms. RSV accounted for the highest virus-associated hospitalization incidence (34.6/10,000, 95% CI 26.3-44.7) and 20% of hospitalizations. There were 11.8/10,000 (95% CI 7.9-18.4) influenza-associated hospitalizations (7% of hospitalizations). RSV and influenza virus detection peaked in winter (November-February) and rainy seasons (July), respectively.

CONCLUSION

Respiratory viruses were associated with a substantial proportion of hospitalizations among young children in a rural Indian community. Public health research and prevention in India should consider targeting RSV and influenza in young children.

Safety and infectivity of two doses of live-attenuated recombinant cold-passaged human parainfluenza type 3 virus vaccine rHPIV3cp45 in HPIV3-seronegative young children

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rHPIV3cp45 vaccine was immunogenic and well-tolerated in seronegative young children.

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A second dose of rHPIV3cp45 given 6 months later was restricted in those previously infected.

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Antibody responses were boosted after a second dose of rHPIV3cp45.

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A second dose of rHPIV3cp45 induced antibody responses in two previously uninfected children.

Background

Human parainfluenza virus type 3 (HPIV3) is a common cause of upper and lower respiratory tract illness in infants and young children. Live-attenuated cold-adapted HPIV3 vaccines have been evaluated in infants but a suitable interval for administration of a second dose of vaccine has not been defined.

Methods

HPIV3-seronegative children between the ages of 6 and 36 months were randomized 2:1 in a blinded study to receive two doses of 10⁵ TCID₅₀ (50% tissue culture infectious dose) of live-attenuated, recombinant cold-passaged human PIV3 vaccine (rHPIV3cp45) or placebo 6 months apart. Serum antibody levels were assessed prior to and approximately 4–6 weeks after each dose. Vaccine virus infectivity, defined as detection of vaccine-HPIV3 in nasal wash and/or a ≥ 4-fold rise in serum antibody titer, and reactogenicity were assessed on days 3, 7, and 14 following immunization.

Results

Forty HPIV3-seronegative children (median age 13 months; range 6–35 months) were enrolled; 27 (68%) received vaccine and 13 (32%) received placebo. Infectivity was detected in 25 (96%) of 26 evaluable vaccinees following doses 1 and 9 of 26 subject (35%) following dose 2. Among those who shed virus, the median duration of viral shedding was 12 days (range 6–15 days) after dose 1 and 6 days (range 3–8 days) after dose 2, with a mean peak log₁₀ viral titer of 3.4 PFU/mL (SD: 1.0) after dose 1 compared to 1.5 PFU/mL (SD: 0.92) after dose 2. Overall, reactogenicity was mild, with no difference in rates of fever and upper respiratory infection symptoms between vaccine and placebo groups.

Conclusion

rHPIV3cp45 was immunogenic and well-tolerated in seronegative young children. A second dose administered 6 months after the initial dose was restricted in those previously infected with vaccine virus; however, the second dose boosted antibody responses and induced antibody responses in two previously uninfected children.

Synergistic combination of clinical and imaging features predicts abnormal imaging patterns of pulmonary infections

We designed and tested a novel hybrid statistical model that accepts radiologic image features and clinical variables, and integrates this information in order to automatically predict abnormalities in chest computed-tomography (CT) scans and identify potentially important infectious disease biomarkers. In 200 patients, 160 with various pulmonary infections and 40 healthy controls, we extracted 34 clinical variables from laboratory tests and 25 textural features from CT images. From the CT scans, pleural effusion (PE), linear opacity (or thickening) (LT), tree-in-bud (TIB), pulmonary nodules, ground glass opacity (GGO), and consolidation abnormality patterns were analyzed and predicted through clinical, textural (imaging), or combined attributes. The presence and severity of each abnormality pattern was validated by visual analysis of the CT scans. The proposed biomarker identification system included two important steps: (i) a coarse identification of an abnormal imaging pattern by adaptively selected features (AmRMR), and (ii) a fine selection of the most important features from the previous step, and assigning them as biomarkers, depending on the prediction accuracy. Selected biomarkers were used to classify normal and abnormal patterns by using a boosted decision tree (BDT) classifier. For all abnormal imaging patterns, an average prediction accuracy of 76.15% was obtained. Experimental results demonstrated that our proposed biomarker identification approach is promising and may advance the data processing in clinical pulmonary infection research and diagnostic techniques.

Respiratory viral infections post-lung transplantation

Community-acquired respiratory viruses (CARVs) are common pathogens in lung transplant recipients. Infection due to these viruses is associated with multiple complications including: rhinitis, pharyngitis, bronchitis, pneumonia, respiratory failure and even death. CARVs have also become increasingly recognized as a risk factor for acute rejection (AR) and bronchiolitis obliterans syndrome (BOS). Newer diagnostic techniques have enhanced the accuracy of diagnosis, but proven treatment options for CARVs are limited. Further insight into the immune response and allograft dysfunction associated with CARV infections is needed in order to develop novel management strategies which can reduce the morbidity and mortality caused by these infectious agents.