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.

Endogenous Endophthalmitis in COVID-19 Patients

Intrinsic endophthalmitis is indeed behavior that causes eye disease that spreads into the bloodstream from a distant primary site. The intraocular disease caused by hematogenous microbial proliferation is known as indigenous endophthalmitis. Extrinsic and intrinsic endophthalmitis are the two types of endophthalmitis that exist. The presence of an external point of entry is linked to extrinsic endophthalmitis. Intrinsic endophthalmitis is a kind of septicemia caused by a blood-borne infection. Endophthalmitis is a disease of all the inner coating of the eyeball except the sclera and cornea, which is accompanied by substantial, increasing vitreous swelling. Endophthalmitis is a severe ocular crisis with severe visual and general consequences. An exterior injury of the entrance, such as injury, operation, or an inflamed cornea, is the most prevalent route of entry for potential pathogens. Endophthalmitis has a complex etiology, with many pathogenic species and substantial regional heterogeneity. The treatment of endophthalmitis has evolved dramatically during the last century. Endophthalmitis induced by direct inoculation dissemination of pathogenic microbes is a rare occurrence that occurs most commonly in sick or disadvantaged people. Intravenous medication usage, diabetes mellitus, immunological impairment, cancer, prolonged hospitalization, or systemic antibiotic therapy have all been linked to a 0.04 percent incidence rate. Haden described metastatic endophthalmitis in a seriously sick patient with pneumococcal cerebrospinal encephalopathy treated with intravenously anti-meningococcal serum in the 1918 volume of the Journal Ophthalmology. Endogenous endophthalmitis, unlike extrinsic endophthalmitis, needs comprehensive systemic antibiotic treatment. In indigenous endophthalmitis, the illness originates not in the eye but elsewhere in the body. As a result, it is necessary to obtain comprehensive cultures. Patients are sometimes unable to carry out their functions in society or household. As a rest, the person cannot cope financially and socially in his environment. Many social and influential factors are disturbed, and the patients are often depressed. Cosmetically the surgeries are not satisfying. Artificial prosthetics can be used, but they're seldom of minimum functional importance. Such interventions can be helpful for the patient. The focus should be made to deliberately save the patients and not just the cosmetic value of the surgery. Persons with chronic endophthalmitis had more excellent eyesight than people with symptomatic or subacute endophthalmitis. Improvements in eyesight were observed in individuals with persistent or subacute keratitis several months after the surgery more frequently than in people with symptomatic endophthalmitis. Nevertheless, in 40 percent of the overall all instances with an abrupt start, there have been no improvements or even decrease in visual acuity.

Development of a Hamster Natural Transmission Model of SARS-CoV-2 Infection

The global pandemic of coronavirus disease (COVID-19) caused by infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to an international thrust to study pathogenesis and evaluate interventions. Experimental infection of hamsters and the resulting respiratory disease is one of the preferred animal models since clinical signs of disease and virus shedding are similar to more severe cases of human COVID-19. The main route of challenge has been direct inoculation of the virus via the intranasal route. To resemble the natural infection, we designed a bespoke natural transmission cage system to assess whether recipient animals housed in physically separate adjacent cages could become infected from a challenged donor animal in a central cage, with equal airflow across the two side cages. To optimise viral shedding in the donor animals, a low and moderate challenge dose were compared after direct intranasal challenge, but similar viral shedding responses were observed and no discernible difference in kinetics. The results from our natural transmission set-up demonstrate that most recipient hamsters are infected within the system developed, with variation in the kinetics and levels of disease between individual animals. Common clinical outputs used for the assessment in directly-challenged hamsters, such as weight loss, are less obvious in hamsters who become infected from naturally acquiring the infection. The results demonstrate the utility of a natural transmission model for further work on assessing the differences between virus strains and evaluating interventions using a challenge system which more closely resembles human infection.

Quality of injectable oxytetracycline circulating in legal markets of Addis Ababa, Ethiopia using physiochemical and sterility analysis

This study was conducted to evaluate the quality of different brands of injectable oxytetracycline solutions circulating in the legal markets of Addis Ababa with respect to physicochemical characteristics and sterility. Nine brands of oxytetracycline with thirteen different batches were randomly purchased from veterinary drug stores in the city. The physical assessment was performed by using a checklist that was prepared based on the World Health Organization guidelines. The qualitative and quantitative analysis of active pharmaceutical ingredients (API) was performed by High-Performance Liquid Chromatography. The sterility test was assessed by using the direct inoculation method. All samples passed the identity, the assay, and the sterility tests. However, there were statistically significant differences (P<0.05) among brands in the quantity of API. The highest percentage of the API was recorded in brand G (112.12%± 1.86) while the lowest was seen in brand H (92.61%± 1.5). This study revealed that all brands passed both physicochemical and sterility tests except for the differences in the API level among brands. Strict regulation, monitoring, and wider-scale surveillance are required to assure sustainable control of substandard, unsterile, and falsified pharmaceutical products in the country.

Infection of a sylvian Galassi II arachnoid cyst after craniotomy for resection of a parasagittal meningioma

Arachnoid cysts are CSF-containing entities that rarely are symptomatic or warrant neurosurgical intervention. In addition, infection of these lesions is an even rarer event, with only four reports in the literature capturing this. In this report, we present the case of a 79-year-old man presenting with paraparesis, secondary to a right parasagittal meningioma, with an incidental asymptomatic right sylvian arachnoid cyst (Galassi type II). The initially planned surgery was postponed for 3 months, due to COVID-19 restrictions, and he was kept on high dose of steroids. Following tumour resection, the patient developed bilateral subdural empyemas with involvement of the arachnoid cyst, requiring bilateral craniotomies for evacuation of the empyemas and drainage of the arachnoid cyst. Suppuration of central nervous system arachnoid cysts is a very rare complication following cranial surgery with the main working hypotheses including direct inoculation from surrounding inflamed meninges or haematogenous spread secondary to systemic bacteraemia, potentiated by steroid-induced immunosuppression. Even though being a rarity, infection of arachnoid cysts should be considered in immunosuppressed patients in the presence of risk factors such as previous craniotomy.

Contemporary clinical isolates of Staphylococcus aureus from pediatric osteomyelitis patients display unique characteristics in a mouse model of hematogenous osteomyelitis

Osteomyelitis can result from the direct inoculation of pathogens into bone during injury or surgery, or from spread via the bloodstream, a condition called hematogenous osteomyelitis (HOM). HOM disproportionally affects children, and more than half of cases are caused by Staphylococcus (S.) aureus . Laboratory models of osteomyelitis mostly utilize direct injection of bacteria into the bone or the implantation of foreign material, and therefore do not directly interrogate the pathogenesis of pediatric hematogenous osteomyelitis. In this study, we inoculated mice intravenously and characterized resultant musculoskeletal infections using two strains isolated from adults (USA300-LAC and NRS384) and five new methicillin-resistant S. aureus isolates from pediatric osteomyelitis patients. All strains were capable of creating stable infections over five weeks, although the incidence varied. Micro-computed tomography (microCT) analysis demonstrated decreases in trabecular bone volume fraction but little effect on bone cortices. Histologic assessment revealed differences in the precise focus of musculoskeletal infection, with varying mixtures of bone-centered osteomyelitis and joint-centered septic arthritis. Whole genome sequencing of three new isolates demonstrated distinct strains, two within the USA300 lineage and one USA100 isolate. Interestingly, this USA100 isolate showed a distinct predilection for septic arthritis, compared to the other isolates tested, including NRS384 and LAC, which more frequently led to osteomyelitis or mixed bone and joint infections. Collectively, these data outline the feasibility of using pediatric osteomyelitis clinical isolates to study the pathogenesis of HOM in murine models and lay the groundwork for future studies investigating strain-dependent differences in musculoskeletal infection.

Sporotrichosis: A brief review

Sporotrichosis is a chronic mycotic infection caused by dimorphic fungus Sporothrix schenckii, a common saprophyte of soil and plant detritus. According to recent phylogenetic studies, it is a complex of at least six cryptic species with distinct biochemical properties, geographical distribution, virulence, disease patterns, and therapeutic response. S. globosa is the commonest isolated strain in India and evidently responsible for most cases of treatment failure. The disease is endemic in tropical/subtropical regions with occasional large breakouts. In India most cases have been reported along the sub-Himalayan regions. The characteristic cutaneous and subcutaneous infection follows traumatic inoculation of the pathogen. Zoonotic transmission attributed to insect/bird bites, fish handling, and bites of animals is perhaps because of wound contamination from infected dressings or indigenous/herbal poultices and so is human-to-human spread. Progressively enlarging papulo-nodule(s) at the inoculation site develop(s) after a variable incubation period which will evolve into fixed cutaneous sporotrichosis or lymphocutaneous sporotrichosis. Primary pulmonary sporotrichosis following inhalation of conidia and osteoarticular sporotrichosis due to direct inoculation are rare forms. Persons with immunosuppression (HIV, immunosuppressive and anticancer therapy) may develop disseminated cutaneous sporotrichosis or systemic sporotrichosis particularly involving central nervous system. Clinical suspicion is the key for early diagnosis and histologic features remain variable. The demonstration of causative fungus in laboratory culture is confirmatory. Oral itraconazole is the currently recommended treatment for all forms of sporotrichosis but saturated solution of potassium iodide is still used as first-line treatment for uncomplicated cutaneous sporotrichosis in resource poor settings. Terbinafine has been found effective in the treatment of cutaneous sporotrichosis in few studies. Amphotericin B is used initially for the treatment of severe or systemic disease, during pregnancy and in immunosuppressed patients until recovery, and follow-on therapy is with itraconazole until complete (mycological) cure. Posaconazole and ravuconazole remain understudied while echinocandins and voriconazole are not effective.

Corneal Culture in Infectious Keratitis: Effect of the Inoculation Method and Media on the Corneal Culture Outcome

Background: To compare two different methods of corneal culture in infectious keratitis: multiple sampling for direct inoculation and enrichment (standard method) and a single sample via transport medium for indirect inoculation (indirect inoculation method). Methods: Prospective inclusion of patients fulfilling predefined criteria of infectious keratitis undergoing corneal culture according to both studied methods in a randomized order. Results: The standard method resulted in a significantly higher proportion of positive culture outcomes among the 94 included episodes of infectious keratitis (61%; 57/94) than the indirect inoculation method (44%; 41/94) (p = 0.002) and a significantly higher proportion of microorganisms than the indirect inoculation method, with a Cohen’s kappa of 0.38 (95% CI: 0.28–0.49) for agreement between the methods. Subanalysis of culture results showed that direct inoculation on gonococcal agar only combined with the indirect inoculation method resulted in a similar rate of culture positive patients and proportion of detected microorganisms to the standard method. Conclusion: Indirect inoculation of one corneal sample cannot replace direct inoculation of multiple corneal samples without loss of information. A combination of directly and indirectly inoculated samples can reduce the number of corneal samples by four without statistically significant differences in culture outcome or in the proportion of detected microorganisms.

Contemporary clinical isolates of Staphylococcus aureus from pediatric osteomyelitis patients display unique characteristics in a mouse model of hematogenous osteomyelitis

Osteomyelitis can result from the direct inoculation of pathogens into bone during injury or surgery, or from spread via the bloodstream, a condition called hematogenous osteomyelitis (HOM). HOM disproportionally affects children, and more than half of cases are caused by Staphylococcus (S.) aureus. Laboratory models of osteomyelitis mostly utilize direct injection of bacteria into the bone or the implantation of foreign material, and therefore do not directly interrogate the pathogenesis of pediatric hematogenous osteomyelitis. In this study, we inoculated mice intravenously and characterized resultant musculoskeletal infections using two strains isolated from adults (USA300-LAC and NRS384) and five new methicillin-resistant S. aureus isolates from pediatric osteomyelitis patients. All strains were capable of creating stable infections over five weeks, although the incidence varied. Micro-computed tomography (microCT) analysis demonstrated decreases in trabecular bone volume fraction but little effect on bone cortices. Histologic assessment revealed differences in the precise focus of musculoskeletal infection, with varying mixtures of bone-centered osteomyelitis and joint-centered septic arthritis. Whole genome sequencing of three new isolates demonstrated distinct strains, two within the USA300 lineage and one USA100 isolate. Interestingly, the USA100 strain showed a distinct predilection for septic arthritis, compared to the USA300 strains, including NRS384 and LAC, which more frequently led to osteomyelitis or mixed bone and joint infections. Collectively, these data outline the feasibility of using pediatric osteomyelitis clinical isolates to study the pathogenesis of HOM in murine models and lay the groundwork for future studies investigating strain-dependent differences in musculoskeletal infection.