Spontaneous pneumomediastinum as a complication in human bocavirus infection

A case report of pneumomediastinum in a COVID-19 patient treated with high-flow nasal cannula and review of the literature: Is this a "spontaneous" complication?

Oxygen support with high-flow nasal cannula (HFNC) is gentler than mechanical ventilation and may provide significant benefits, but more studies are needed to investigate the efficacy and safety of different respiratory supports in patients with COVID-19 pneumonia.

Epidemiology of HBoV1 infection and relationship with meteorological conditions in hospitalized pediatric patients with acute respiratory illness: a 7-year study in a subtropical region

BACKGROUND

Human bocavirus 1 (HBoV1) is an important cause of acute respiratory illness (ARI), yet the epidemiology and effect of meteorological conditions on infection is not fully understood. To investigate the distribution of HBoV1 and determine the effect of meteorological conditions, hospitalized pediatric patients were studied in a subtropical region of China.

METHODS

Samples from 11,399 hospitalized pediatric patients (≤14 years old), with ARI were tested for HBoV1 and other common respiratory pathogens using real-time PCR, between July 2009 and June 2016. In addition, local meteorological data were collected.

RESULTS

Of the 11,399 patients tested, 5606 (49.2%) were positive for at least one respiratory pathogen. Two hundred forty-eight of 11,399 (2.2%) were positive for HBoV1 infection. Co-infection was common in HBoV1-positive patients (45.2%, 112/248). A significant difference in the prevalence of HBoV1 was found in patients in different age groups (p < 0.001), and the peak prevalence was found in patients aged 7-12 months (4.7%, 56/1203). Two HBoV1 prevalence peaks were found in summer (between June and September) and winter (between November and December). The prevalence of HBoV1 was significantly positively correlated with mean temperature and negatively correlated with mean relative humidity, and the mean temperature in the preceding month had better explanatory power than the current monthly temperature.

CONCLUSIONS

This study provides a better understanding of the characteristics of HBoV1 infection in children in subtropical regions. Data from this study provide useful information for the future control and prevention of HBoV1 infections.

Spontaneous pneumomediastinum. Case report

Introducción: se define neumomediastino espontáneo (NE) a la presencia de aire en el intersticio mediastinal. Es una entidad rara, considerada benigna y autolimitada que afecta, en la mayoría de los casos, a adultos jóvenes. Su diagnóstico es clínico y radiológico.Descripción del caso: hombre de 21 años de edad con tos y expectoración verdosa de cuatro días, síntomas asociados a disnea, dolor torácico, fiebre y enfisema subcutáneo supraclavicular bilateral. La radiografía tórax sugirió neumomediastino, el cual fue confirmado por tomografía. El paciente fue hospitalizado para observación y tratamiento. Luego de una evolución positiva, fue dado de alta al sexto día.Discusión: el NE es un diagnóstico diferencial en pacientes que consultan por dolor torácico y disnea. Su prevalencia es inferior a 0.01% y su mortalidad es baja. Debe sospecharse en pacientes con dolor torácico y enfisema subcutáneo al examen físico. Entre 70 y 90% de los casos pueden identificarse mediante radiografía de tórax, mientras que su confirmación puede obtenerse a través de tomografía de tórax. En la mayoría de casos no requiere estudios adicionales.Conclusión: el NE es una causa poco conocida de dolor torácico agudo, rara vez se tiene en cuenta como diagnóstico diferencial; es auto limitado y tiene buen pronóstico.

Dyspnoea and chest pain as the presenting symptoms of pneumomediastinum: two cases and a review of the literature

Pneumomediastinum is the presence of air in the mediastinum. It may occur as spontaneous, traumatic, or iatrogenic pneumomediastinum. Although spontaneous pneumomediastinum is usually observed in healthy young men, traumatic pneumomediastinum may be caused by blunt or penetrating trauma to the chest and neck. Pneumomediastinum is a clinical condition with potential complications that cause high morbidity and mortality rates. Pneumomediastinum also may develop without tracheal or oesophageal injury after spontaneous or blunt chest, neck and facial injuries, and it may be accompanied by pneumothorax. We treated two patients who had pneumomediastinum. Case 1 was a 20-year-old man who had pain and dyspnoea around the sternum for one hour, as a result of a blow from an elbow during a football match. Case 2 was a 23-year-old man who had a two-day history of dyspnoea and chest pain with no history of trauma. In both patients, diagnosis of pneumomediastinum was confirmed with thoracic computed tomography scans, and the condition resolved within five days of in-patient observation. In conclusion, the diagnosis of pneumomediastinum should be considered for all patients who present to the emergency department with chest pain and dyspnoea.

Pneumomediastinum, pneumorrhachis and subcutaneous emphysema associated with viral infections: Report of three cases

Spontaneous pneumomediastinum is usually secondary to alveolar rupture in the pulmonary interstitium, associated with subcutaneous emphysema and occasionally with pneumothorax, but is rarely associated with pneumorrhachis. The leaked air into the pulmonary perivascular interstitium follows the path of least resistance from the mediastinum to the fascial planes of the neck. Air freely communicates via the neural foramina and collects in the epidural space. Pneumorrhachis is defined as the presence of air in the spinal canal, either in the intradural and/or extradural spaces. It is a very rare clinical entity and mostly asymptomatic, hence most probably underdiagnosed. Many pathological and physiological events can lead to alveolar rupture, and these clinical findings can be related to various, mainly traumatic and iatrogenic etiologies. Herein we report three cases of pneumomediastinum, subcutaneous emphysema, interstitial emphysema and pneumorrhachis in two cases, which were related to rhinovirus, human bocavirus and respiratory syncytial virus infection.

Human bocaviruses: Possible etiologic role in respiratory infection

Four species of human bocaviruses (HBoV) are currently included in the Bocavirus genus. There is satisfactory evidence demonstrating an association between HBoV1 and respiratory disease in children, and there is evidence that HBoV2 (and possibly the HBoV3 and HBoV4 species) are associated with gastroenteritis. In particular, HBoV1 has been associated with a prolonged period of persistence in the mucosa of the respiratory tract. Virus persistence does play a role in the high frequency of co-infections with proper pathogens of the upper and lower respiratory tracts. The high detection rate of multiple respiratory viruses in up to 83% of respiratory specimens and the presence of asymptomatic HBoV1 infections complicate the elucidation of the pathogenic role of the agent. Overall, a large amount of data are available concerning HBoV1, whereas little information is available about other bocavirus species. High viral loads are often associated with symptoms, and viremia may be associated with systemic manifestations such as encephalopathy. The effects and mechanisms of latency, persistence, reactivation, and reinfection are poorly understood. Thus, particularly in co-infections, the pathogenic contribution of the detected bocavirus species cannot be accurately stated. This review summarizes the current knowledge of HBoV species and provides perspectives for future clinical studies.