Klinische Symptomatik und Verlauf viraler Atemwegsinfekte bei Säuglingen

Lower respiratory infections cause significant health care costs annually and are still the most common cause of death among infants worldwide to this day. Nevertheless, there is no uniform treatment regimen and many of the pathogenesis is still not understood. We examined the clinical course including the complications, as well as the necessary therapies in 206 infants treated in our clinic due to specific viral infection of the lower respiratory tract from October 2017 up to March 2020. The virus detection was carried out by means of a multiplex PCR (FTDTM Respiratory Pathogens 21 by Siemens) from a nasopharyngeal smear. We were able to show that RSV infections, in contrast to non- RSV, generally, were more likely to occur in younger infants aggravated with bronchiolitis and a slightly prolonged hospital confinement. Some other individual viruses were an exception in terms of typical age. The age of RSV and HBoV corresponded to each other and infections caused by HEV and HPIV overall affected the youngest infants. The viral percentage of pneumonia was predominantly caused by viruses other than RSV with enterovirus showing the highest incidence. Obstructive bronchitis was significantly more common and viral croup caused by other viruses, aside from RSV was identified. Furthermore, RSV infections were also found to be associated with increased oxygen demand. Atelectasis occurred with similar frequency in the monoinfections and in the non-RSV mixed infections. The exception in terms of frequency was the Bocavirus at 40%, with a significantly higher risk than with other monoinfections. It was shown that all pathogens identified with infants under 6 months of age can cause central apnea. We could show that the risk, contrary to expectations, was higher with a non-RSV monoinfection than with RSV. Mixed infections without RSV increased this risk again. The most common apneas, however, were caused by parainfluenza monoinfections. The significantly less common mixed infections with and without RSV had a more serious course, in general. They were those with prolonged hospitalizations and with increased complications in the form of more frequent use of antibiotics and associated with airway obstruction. The RSV co-infections, likewise, showed another severe complication with additionally increased infiltrates and atelectasis. The need for additional oxygen supply was also most common in mixed RSV infections. We were able to show that monoinfections without RSV as compared to RSV significantly improved condition with salbutamol and atrovent, as well as with systemic corticosteroids treatments. It benefits specifically those who had infections caused by bocaviruses. These treatment options were necessary among the majority of the patients. Mixed infections also often improved with salbutamol, and the co-infections with RSV, were slightly improved. Bacterial superinfections were rare with only 8.3%. As a whole, there was no difference among most mono-infections. Only an infection with HPIV or HMPV seemed to be associated with an increased risk as related to monoinfections and all mixed infections. Due to their rarity, antibiotics should be used cautiously and only if there is definite evidence of bacterial infection, in order to counteract the development of multi-resistant germs.