Spontaneous resolution and bone regeneration in hemophilic pseudotumor: A rare case report and literature review.

AIM: Hemophilic pseudotumor (HP) is a very rare complication of hemophilia seen in only 1-2% of the cases. Although it is much more common in long bones, pelvis and small bones of hands and feet and very rarely involving jaw bones. METHOD AND RESULT: In the present case, the presence of a rare hemophilic pseudotumor of the mandible with the positive history of Hemophilia B justifies that the history, clinical and radiological examinations were sufficient to arrive at conclusive diagnosis precluding invasive diagnostic procedures such as biopsy hence avoiding the risk of hemorrhage, infection, or fistula. This case also highlights that patient was conservatively managed with Factor IX replacement alone with a very good clinical outcome. CONCLUSION: HP should be considered as a differential diagnosis of any progressive swelling of hard and soft tissues occurring in a patient with severe haemophilia.

Evidence of self-resolution of feline trichomonosis in a pair of single household cats due to ronidazole-resistant Tritrichomonas foetus.

Tritrichomonas foetus causes chronic large-bowel diarrhoea in cats, complicated not only by its chronicity but for its difficulty to treat, with few registered or effective products available, subsequently resulting in ronidazole frequently used off-label. The extent of T. foetus resistance to ronidazole is unknown. To demonstrate in vitro resistance of feline T. foetus to ronidazole and the self-resolution of the infection, we isolated novel T. foetus "feline" genotype strains from two cats in 2017 from the same household and monitored these cats over a three-year period. Axenic cultures of T. foetus from the cats were tested for in vitro resistance to metronidazole and ronidazole using anaerobic and aerobic culture assays. The minimum lethal concentration for the novel strains after incubation in aerobic conditions for 48 h were 50-100 µg/ml and 6.25-12.50 µg/ml for metronidazole and ronidazole, respectively. For susceptible T. foetus strains, the minimum lethal concentrations ranged from 1.56-12.50 µg/ml for metronidazole, and 0.39-3.13 µg/ml for ronidazole. The self-resolution of the infection was assessed using repeat diagnostic qPCR and culture. Whilst positive in 2018, the cat samples are no longer returning positive qPCR results in 2020 and 2021, indicating self-resolution over this period. This study demonstrated resistance to ronidazole for the first time in Australian cats and infection self-resolution without antimicrobial intervention is demonstrated. This study provides clinicians with the evidence to reduce the use of off-label ronidazole, and advice on the resolution timeframe for cats in single households.

Self-resolving prepontine cyst.

BACKGROUND: Intracranial prepontine cysts are rare and include epidermoid cysts, arachnoid cysts, and neurenteric cysts. Symptomatic prepontine cysts may require surgical intervention. Reports of spontaneous resolution of cysts are rare. CASE DESCRIPTION: We describe the case of a young gentleman who presented with headache and fever. Magnetic resonance imaging of the brain identified a prepontine lesion with features consistent with epidermoid cyst. During admission, the patient received symptomatic management in addition to empirical antibiotic therapy and dexamethasone. The patient improved symptomatically in the next 48 hours and was discharged. Follow-up imaging at 6 months and 1 year showed significant reduction in size of the lesion. CONCLUSION: For asymptomatic prepontine cysts, a close radiological and clinical follow-up may prove useful.

Endogenous expression pattern of resolvin D1 in a rat model of self-resolution of lipopolysaccharide-induced acute respiratory distress syndrome and inflammation.

Resolvin D1 (RvD1), an endogenous lipid mediator derived from docosahexaenoic acid, has been reported to promote a biphasic activity in anti-inflammatory response and regulate inflammatory resolution. The present study aimed to determine the endogenous expression pattern of RvD1 in a rat model of self-resolution of lipopolysaccharide (LPS)-induced acute respiratory distress syndrome (ARDS) and inflammation. The ARDS model was induced by administrating LPS (2mg/kg) via tracheotomy in 138 male Sprague-Dawley rats. At specified time points, lung injury and inflammation were respectively assessed by lung histology and analysis of bronchoalveolar lavage fluid and cytokine levels. The expression of endogenous RvD1 was detected by high performance liquid chromatography and tandem mass spectrometry. The results showed that histological lung injury peaked between 6h (LPS6h) and day 3, followed by recovery over 4-10 days after LPS administration. Lung tissue polymorph nuclear cell (PMN) was significantly increased at LPS6h, and peaked between 6h to day 2. The levels of interleukin (IL)-6 and IL-10 were significantly increased at LPS6h and remained higher over day 10 as compared to baseline. Intriguingly, the endogenous RvD1 expression was decreased gradually during the first 3 days, followed by almost completely recovery over days 9-10. The finding indicated that endogenous RvD1 underwent a decrease in expression followed by gradual increase that was basically coincident with the lung injury recovery in a rat model of self-resolution LPS-induced ARDS and inflammation. Our results may help define the optimal therapeutic window for endogenous RvD1 to prevent or treat LPS-induced ARDS and inflammation.