A systematic review of epidemiologic studies on scabies in the Philippines

Background and Objective@#Scabies is the second most common cause of disability due to skin disease in the Philippines. However, there were no cited studies in Global Burden of Disease 2019 and the disability-adjusted life years (DALY) computations were most likely based on statistical modelling. The Philippine Department of Health has embarked on a program to estimate the disease burden of priority diseases in the country, which include scabies. The last nationwide prevalence survey was 23 years ago. This systematic review aimed to estimate the prevalence or incidence of scabies in the Philippines. @*Methods@#We searched PubMed, Scopus, Herdin, and Philippine Health Research Registry (search date October 2022) for studies on prevalence/incidence (including systematic reviews, cross-sectional studies, cohort studies, case series, registry or census studies) of patients diagnosed with scabies in the Philippines. We excluded narrative reviews, commentaries, and conference proceedings or abstracts. Two reviewers independently screened titles and abstracts, assessed full text reports for eligibility, appraised the quality of included studies, and collected data using a pretested data extraction form. We did not pool studies due to clinical heterogeneity but plotted the individual studies in a forest plot with prevalence estimates and confidence intervals. We reported the median and interquartile range for entire group or relevant subgroups (age, setting) of studies. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess the certainty of evidence.@*Results@#We included nine studies (N=79,065). Most were clinic-based prevalence studies, retrospective chart reviews, conducted in dermatology outpatient clinics, Metro Manila area, and on pediatric populations. Prevalence of scabies was moderate (i.e., between 2 and 10%), ranging from 2.75% (national prevalence survey) to 6.8% (communitybased review), to high (> 10%) among pediatric patients in clinic-based retrospective chart reviews (29 to 36%) and institution-based surveys (39.0% to 45%), and a tertiary government university training hospital dermatology clinic (22.9%). The most affected age group was from 0 to 14 y/o, while males tended to have a higher prevalence than females. The cooler month of January had higher prevalence than the hotter month of June in one study. @*Conclusion@#Scabies is common in the Philippines, especially among children and elderly in institutional settings, and during the month of January. There is a need to do a national prevalence survey to identify high-risk areas and to monitor the prevalence of scabies, especially in crowded settings and vulnerable populations. This information can be used for estimating the burden of disease for scabies and guide appropriate health resource allocation.

Glomangiopericytoma: The sinonasal mimic of soft tissue hemangiopericytoma

@#A 42-year old Filipino male with a 10-month history of progressive left nasal obstruction and rhinorrhea and a clinical impression of nasal polyposis underwent endoscopic sinus surgery with partial ethmoidectomy and polypectomy. We received several dark-brown, irregular, rubbery tissue fragments with an aggregate diameter of 3 cm. Histopathologic examination shows sheets of spindly tumor cells beneath the respiratory epithelial lining. These spindle cells are closely packed and arranged in short fascicles and storiform clusters surrounding hyalinized large vessels or thin-walled submucosal blood vessels. (Figures 1 and 2) There is no atypia or necrosis. Immunohistochemical studies show strong immunoreactivity to muscle specific actin, and focal reactivity to S-100. (Figure 3) Stains for CD34, caldesmon, cytokeratin, and desmin, are negative. (Figure 4) Based on these features, we diagnosed the case as glomangiopericytoma. Glomangiopericytoma is a rare tumor arising from the pericytes surrounding capillaries, and accounts for less than 0.5% of all sinonasal tumors.1 It has a very slight female preponderance, with a peak incidence during the seventh decade of life. The most common symptom is nasal obstruction, or epistaxis, with accompanying difficulty breathing, sinusitis and headache. A mass, or polyp is the most common clinical finding.2 Hematoxylin–eosin staining shows a well-delineated but unencapsulated cellular tumor underneath the normal respiratory epithelium that effaces or surrounds adjacent normal structures.2 The tumor is composed of closely packed, uniform, oval to spindle-shaped cells, in short fascicles and in storiform, whorled or palisaded patterns. The cells surround numerous branching thin-walled, blood vessels, thus the morphologic resemblance to soft tissue hemangiopericytoma/solitary fibrous tumor. However, in contrast to hemangiopericytoma, glomangiopericytoma shows diffuse reactivity to muscle actins, and non-reactivity to CD34, while hemangiopericytoma shows the reverse reactions. Desmin and caldesmon are likewise non-reactive, distinguishing the tumor from leiomyomas or leiomyosarcomas of the upper aerodigestive tract. Cytokeratin non-reactivity distinguishes it from spindle cell carcinoma. S100, although typically negative, can be focally and weakly positive in a small percentage of tumor.3 Glomangiopericytoma is categorized as a borderline low malignancy tumor with an overall survival of >90% in 5 years but which tends to recur in up to 30% of cases. Strict follow-up is thus required, especially if complete resection is not achieved.1