Pediatric orbital cellulitis: Case report of an unusual etiology and pathogen.

Orbital cellulitis is an uncommon condition with risks to sight and life. As a complication of maxillofacial injuries, the literature suggests this is only possible with fractures or direct inoculation, and there are no reports to the contrary. Here, we make the first report of a possible etiology by which orbital cellulitis developed in a 14-year-old boy even without skin breach or bony fractures; as well as a rare causative pathogen. He presented with facial abscess and progressive orbital cellulitis after blunt facial trauma, requiring functional endoscopic sinus surgery with needle aspiration of facial abscess externally. Cultures showed growth of Streptococcus constellatus/Parvimonas micra, and he received further antibiotics with full recovery.The pathophysiology of orbital cellulitis in this patient is attributed to vascular congestion and local pressure from maxillofacial contusion and maxillary hemoantrum, with impaired paranasal sinus ventilation encouraging anaerobic bacterial growth. Further progression led to facial abscess formation and intraorbital spread with orbital cellulitis. The pediatric demographic is injury-prone, and self-reporting of symptoms can be delayed. Hence, increased suspicion of complicated injuries and orbital cellulitis may be required when managing maxillofacial contusions so that prompt treatment can be given.

A Ten-Year Review of Audiological Performance in Children with Inner Ear Abnormalities after Cochlear Implantation in Singapore.

OBJECTIVES: To evaluate children with inner ear malformations following cochlear implantation (CI) in a tertiary pediatric hospital in Singapore to identify factors influencing outcomes after CI. METHODS: This is a retrospective cohort study of children aged 0 to 18 years, who had CI between 2000 and 2013. Demographic information, data on risk factors, type of inner ear malformation (IEM), age at implantation, speech pre- and postimplantation, and duration of follow-up were collected from clinical records. Operative details and audiological outcomes were also analyzed. RESULTS: A total of 70 children underwent 83 CI surgeries. The mean age of the patients was 4.05 ± 3.17 years (range 1-18 years). Twenty patients (28.57%) had abnormal CT scan findings. CSF gusher occurred in 15 out of 26 CI (57.69%) in the group with IEM. Nine out of twenty patients (45.00%) had poor IT-MAIS scores prior to implantation. The average preoperative IT-MAIS score for children with anomalous inner ear anatomy was 14.1. The older CI patients, 3/20 (15.00%), mean age 8.33 years (range 7-10 years), were mostly referred for persistently unclear speech following hearing aids. Eleven patients (55.00%) had good speech and aided hearing threshold within speech limits after CI and were eligible for reintegration into mainstream schools. Five patients (25.00%) had improvement in speech but continued to receive education in special schools. Four patients (20.00%) had poor progress after surgery. CONCLUSION: The presence of absent cochlear nerve, electrode folding, and underlying neurological disorders seemed to be associated with poorer outcomes.

Human Innate Lymphoid Cell Subsets Possess Tissue-Type Based Heterogeneity in Phenotype and Frequency.

Animal models have highlighted the importance of innate lymphoid cells (ILCs) in multiple immune responses. However, technical limitations have hampered adequate characterization of ILCs in humans. Here, we used mass cytometry including a broad range of surface markers and transcription factors to accurately identify and profile ILCs across healthy and inflamed tissue types. High dimensional analysis allowed for clear phenotypic delineation of ILC2 and ILC3 subsets. We were not able to detect ILC1 cells in any of the tissues assessed, however, we identified intra-epithelial (ie)ILC1-like cells that represent a broader category of NK cells in mucosal and non-mucosal pathological tissues. In addition, we have revealed the expression of phenotypic molecules that have not been previously described for ILCs. Our analysis shows that human ILCs are highly heterogeneous cell types between individuals and tissues. It also provides a global, comprehensive, and detailed description of ILC heterogeneity in humans across patients and tissues.

A High-Dimensional Atlas of Human T Cell Diversity Reveals Tissue-Specific Trafficking and Cytokine Signatures.

Depending on the tissue microenvironment, T cells can differentiate into highly diverse subsets expressing unique trafficking receptors and cytokines. Studies of human lymphocytes have primarily focused on a limited number of parameters in blood, representing an incomplete view of the human immune system. Here, we have utilized mass cytometry to simultaneously analyze T cell trafficking and functional markers across eight different human tissues, including blood, lymphoid, and non-lymphoid tissues. These data have revealed that combinatorial expression of trafficking receptors and cytokines better defines tissue specificity. Notably, we identified numerous T helper cell subsets with overlapping cytokine expression, but only specific cytokine combinations are secreted regardless of tissue type. This indicates that T cell lineages defined in mouse models cannot be clearly distinguished in humans. Overall, our data uncover a plethora of tissue immune signatures and provide a systemic map of how T cell phenotypes are altered throughout the human body.

Mapping the Diversity of Follicular Helper T Cells in Human Blood and Tonsils Using High-Dimensional Mass Cytometry Analysis.

Single-cell analysis technologies such as mass cytometry allow for measurements of cellular heterogeneity with unprecedented dimensionality. Here, we applied dimensionality reduction and automated clustering methods on human T helper (T(H)) cells derived from peripheral blood and tonsils, which showed differential cell composition and extensive T(H) cell heterogeneity. Notably, this analysis revealed numerous subtypes of follicular helper T (T(FH)) cells that followed a continuum spanning both blood and tonsils. Furthermore, we identified tonsillar CXCR5(lo)PD-1(lo)CCR7(lo) T(FH) cells expressing interferon-γ (IFN-γ), interleukin-17 (IL-17), or Foxp3, indicating that T(FH) cells exhibit diverse functional capacities within extrafollicular stages. Regression analysis demonstrated that CXCR5(lo)PD-1(-) and CXCR5(lo)PD-1(lo) cells accumulate during childhood in secondary lymphoid organs, supporting previous findings that these subsets represent memory T(FH) cells. This study provides an in-depth comparison of human blood and tonsillar T(FH) cells and outlines a general approach for subset discovery and hypothesizing of cellular progressions.

Preauricular sinuses in the pediatric population: techniques and recurrence rates.

AIM: To review the outcomes of two surgical techniques in the management of preauricular sinus in the pediatric population. METHODS: The clinical records of pediatric patients who underwent surgical excision of preauricular sinus in the Department of Otolaryngology of KK Children's and Women's Hospital between January 1997 and March 2009 were retrospectively reviewed. Patients were categorized into two groups, based on the method used for sinus tract visualization or delineation: (1) Microscope group and (2) methylene blue dye and probe group. The latest information on recurrence of preauricular sinus and complications after surgery were updated by phone interview. RESULTS: 208 out of 305 preauricular sinuses were included in this study (n=114 in microscope group; n=94 in methylene blue dye and probe group). 97 cases were excluded as these patients were not contactable by phone or had inadequate data from the clinical records. The mean age of the patients is 6.5 years old. The overall recurrence rate was 2.4% (95% confidence interval (CI) 0.010-0.055) and the overall complication rate was 6.3% (CI 0.037-0.104). Surgical excision with microscope guidance had significantly lower recurrence rate (0.9%) compared to surgical excision with methylene blue dye and probe guidance (4.3%), with an odds ratio of 28.4 (CI 1.22-659.99, P=0.037). The complication rates were not statistically significant between the two groups. The recurrence and complication rates were not significantly affected by race, gender, sex, location of sinus, indication for surgery, history of previous sinus excision, presence of infection during surgery and duration of surgery. CONCLUSION: Surgical excision of preauricular sinus under microscope guidance and under methylene blue and probe guidance in our series had very low overall recurrence and complication rates compared to that reported in the literature. The microscope group had a lower recurrence rate in comparison to that of the methylene blue and probe group.