A 5-year-old girl had poor growth and unresolving pneumonia. There was persistent collapse-consolidation of the right middle lobe. CT thorax revealed bilateral bronchial wall thickening and dilatation. Bronchoscopy showed numerous endobronchial mucosal nodules, consisting of dense lymphoid infiltrates. Bacterial culture of the nodule biopsy suggested endobronchial actinomycosis. She had T-cell lymphopenia. Genetic test confirmed the diagnosis of activated phosphatidylinositol 3-kinase delta syndrome (APDS), an immunodeficiency condition.

Background: The 5th wave of the COVID-19 pandemic in Hong Kong was dominated by the omicron variant, which may have more upper airway involvement affecting children. This pilot study aims at analyzing any associations between the COVID-19-omicron-variant and croup in children. Methods: This retrospective study reviewed electronic medical records of patients admitted to Tuen Mun Hospital of Hong Kong from 1 January 2018 to 31 March 2022 with diagnostic code of croup (ICD-10 code J05.0). Patients were categorized into non-COVID period (1 January 2018 - 31 December 2019); COVID-pre-omicron period (1 January 2020 - 31 December 2021) and COVID-omicron period (1 January 2022- 31 March 2022). Disease associations and severity were compared through incidence rates, Westley Croup Severity Score, length of hospital stay, medications use, respiratory support and intensive care unit admissions. Results: The rate of infection of COVID-19 in croup patients admitted during COVID-omicron period (90%) was significantly higher than those in the COVID-pre-omicron period (3.6%, p< 0.001). They also had a higher Westley Score (moderate + severe disease: COVID-omicron: 56.7%; COVID-pre-omicron: 22.4%; p=0.004; non-COVID: 24.8%, p< 0.001), longer hospital stay (median: COVID-omicron 3.00 days ; COVID-pre-omicron:2.00 days, p<0.001, non-COVID: 2.00 days, p=0.034) , and higher dexamethasone requirements (mean : COVID-omicron = 0.78mg/kg; COVID-pre-omicron= 0.49mg/kg, p < 0.001; non-COVID =0.58mg/kg , p=0.001) while compared to those of the COVID-pre-omicron period and non-COVID period. Conclusion: The omicron variant of COVID-19 is a significant contributing factor to croup and can lead to more severe disease in children of Hong Kong.

The aim is to look at the rate of macrolide resistance in a group of children admitted with mycoplasma pneumonia at a local hospital and to compare and analyze clinical features of macrolide-resistant Mycoplasma pneumoniae (MRMP) and macrolide-sensitive Mycoplasma pneumoniae (MSMP) to facilitate early recognition of likely resistance and to guide the choice of appropriate antibiotics for treatment. Paediatric patients with pneumonia with a real time mycoplasma PCR positive result were analyzed. Mutations associated with macrolide resistance were identified by direct DNA sequencing of the domain V of the 23S rRNA gene and patient. MRMP was identified in 43% of the patients tested within March 2013 to August 2013. No single clinical characteristic or laboratory markers were reliable in differentiating between MSMP and MRMP. A clinical parameter of non-defervescence at 72 hours was identified as a good clinical indicator for likely macrolide resistance. 96% of MSMP patients achieved defervescence by 72 hours. There were 5 patients that developed pleural effusion and 80% of them belonged to the MRMP group. All of the 15 patients treated with doxycycline, were able to achieve rapid defervescence within 24 hours. The overall length of stay was longer in the MRMP group. Macrolide resistance in Hong Kong appears to be lower than previous published data. With limited laboratory support to identity resistance, clinical parameters help facilitate and support the decision for alternative treatment options such as doxycycline to prevent complications and prolong length of stay in a common and treatable condition in the paediatric population.