Anti-TRPM1 autoantibody-positive unilateral melanoma associated retinopathy (MAR) triggered by immunotherapy recapitulates functional and structural details of TRPM1-associated congenital stationary night blindness.

Purpose: To describe the retinal phenotype of an unusual case of anti-TRPM1 autoantibody-positive unilateral melanoma-associated retinopathy (MAR) triggered by nivolumab therapy and compare with the phenotype of TRPM1-associated Congenital Stationary Night Blindness (TRPM1-CSNB). Observations: Unilateral MAR was diagnosed 3 months after starting nivolumab therapy for consolidation of a successfully treated melanoma. Retinal autoantibodies against TRPM1 were identified. ffERG, microperimetry and static chromatic perimetry confirmed unilateral ON-Bipolar Cell (ON-BPC) dysfunction and central rod sensitivity losses in the left eye; the contralateral eye was normal. There was borderline ganglion cell (GCL) and inner nuclear layer (INL) thinning, but a significantly thinner inner plexiform layer (IPL) in the affected compared to the unaffected eye. Longitudinal reflectivity profiles (LRPs) demonstrated an abnormal inner plexiform layer (IPL) lamination in the involved eye. Nearly identical changes were documented in two cases of TRMP1-cCSNB and in a case of anti-TRPM1 autoantibody-negative MAR. The functional changes partially recovered with discontinuation of the medication without added immunosuppression. Conclusions and Importance: Comparisons between the affected and unaffected eye in this unilateral MAR case revealed inner retinal abnormalities and abnormal lamination of the IPL associated with the classical retina-wide ON-BPC dysfunction, and localized central rod-mediated sensitivity losses. A nearly identical structural phenotype in two cases of cCSNB and a case of anti-TRPM1 autoantibody-negative MAR supports a specific structural-functional phenotype for these conditions with ON-BPC dysfunction.

Treatment of Spontaneous Tumors With Algorithmically Controlled Electroporation.

OBJECTIVE: To study the safety and efficacy of algorithmically controlled electroporation (ACE) against spontaneous equine melanoma. METHODS: A custom temperature sensing coaxial electrode was paired with a high voltage pulse generation system with integrated temperature feedback controls. Computational modeling and ex vivo studies were conducted to evaluate the system's ability to achieve and maintain target temperatures. Twenty-five equine melanoma tumors were treated with a 2000 V protocol consisting of a 2-5-2 waveform, 45 °C temperature set point, and integrated energized times of 0.005 s, 0.01 s, or 0.02 s (2500x, 5000x, and 10000x 2 µs pulses, respectively). Patients returned 20-50 days post treatment to determine the efficacy of the treatment. RESULTS: ACE temperature control algorithms successfully achieved and maintained target temperatures in a diverse population of spontaneous tumors with significant variation in tissue impedance. All treatments were completed successfully without and without adverse events. Complete response rates greater than 93% were achieved in all treatment groups. CONCLUSION: ACE is a safe and effective treatment for spontaneous equine melanoma. The temperature control algorithm enabled rapid delivery of electroporation treatments without prior knowledge of tissue electrical or thermal properties and could adjust to real time changes in tissue properties. SIGNIFICANCE: Real time temperature control in electroporation procedures enables treatments near critical structures where thermal damage is contraindicated. Unlike standard approaches, ACE protocols do not require extensive pretreatment planning or knowledge of tissue properties to determine an optimal energy delivery rate and they can account for changes in tissue state (e.g., perfusion) in real time to simultaneously minimize treatment time and potential for thermal damage.

Investigation of integrated time nanosecond pulse irreversible electroporation against spontaneous equine melanoma.

Introduction: Integrated time nanosecond pulse irreversible electroporation (INSPIRE) is a novel tumor ablation modality that employs high voltage, alternating polarity waveforms to induce cell death in a well-defined volume while sparing the underlying tissue. This study aimed to demonstrate the in vivo efficacy of INSPIRE against spontaneous melanoma in standing, awake horses. Methods: A custom applicator and a pulse generation system were utilized in a pilot study to treat horses presenting with spontaneous melanoma. INSPIRE treatments were administered to 32 tumors across 6 horses and an additional 13 tumors were followed to act as untreated controls. Tumors were tracked over a 43-85 day period following a single INSPIRE treatment. Pulse widths of 500ns and 2000ns with voltages between 1000 V and 2000 V were investigated to determine the effect of these variables on treatment outcomes. Results: Treatments administered at the lowest voltage (1000 V) reduced tumor volumes by 11 to 15%. Higher voltage (2000 V) treatments reduced tumor volumes by 84 to 88% and eliminated 33% and 80% of tumors when 500 ns and 2000 ns pulses were administered, respectively. Discussion: Promising results were achieved without the use of chemotherapeutics, the use of general anesthesia, or the need for surgical resection in regions which are challenging to keep sterile. This novel therapeutic approach has the potential to expand the role of pulsed electric fields in veterinary patients, especially when general anesthesia is contraindicated, and warrants future studies to demonstrate the efficacy of INSPIRE as a solid tumor treatment.

Bilateral patellar aplasia in a foal.

A 2-day-old Cleveland Bay colt was referred to the Equine Emergency Service of the Farm Animal and Equine Veterinary Medical Center at North Carolina State University's College of Veterinary Medicine for evaluation of decreased nursing behaviour and right hindlimb lameness of 2 days' duration. When assisted to stand, the foal was unable to extend either hindlimb or bear weight on the hindlimbs, the right patella was luxated laterally and unable to be reduced, and the foal assumed a crouched position. Stifle radiographs revealed minimal, heterogeneous, ill-defined ossification of both patellae. Due to the severity of the musculoskeletal defects, humane euthanasia was elected. Post-mortem examination identified a congenital malformation of both patella bones with failure of ossification and cardiac changes suggestive of right atrioventricular valve dysplasia. Histology of the patellae showed no evidence of osteoid deposition or ossification. To our knowledge, bilateral congenital patellar aplasia has not been previously described in foals.

Fleck-like lesions in CEP290-associated leber congenital amaurosis: a case series.

PURPOSE: To provide a detailed ophthalmic phenotype of a small cohort of patients with Leber Congenital Amaurosis (LCA) caused by mutations in CEP290 (CEP290-LCA) with a focus on elucidating the origin of yellow-white lesions observed in 30% of patients with this condition. METHODS: This is a retrospective review of records of five patients with CEP290-LCA. Patients had comprehensive ophthalmic evaluations. Visual function was assessed with full-field electroretinograms (ffERGs) and full-field sensitivity testing (FST). Multimodal imaging was performed with spectral domain optical coherence tomography (SD-OCT), fundus autofluorescence (FAF) with short- (SW) and near-infrared (NIR) excitation wavelengths. RESULTS: All patients showed relative structural preservation of the foveal and near midperipheral retina separated by a pericentral area of photoreceptor loss. Yellow-white, fleck-like lesions in an annular distribution around the near midperiphery co-localized with hyperreflective lesions on SD-OCT. The lesions located between the inner segment ellipsoid signal and the apical retinal pigment epithelium (RPE). The inner retina was normal. Longitudinal observations in one of the patients indicates the abnormalities may represent an intermediate stage in the degenerative process between the near normal appearing retina previously documented in young CEP290-LCA patients and the pigmentary retinopathy observed along the same region in older individuals. CONCLUSIONS: We speculate that fleck-like lesions in CEP290-LCA correspond to malformed, rudimentary or degenerated, including shed, photoreceptor outer segments. The topography and possible origin of the abnormalities may inform the planning of evolving genetic therapies for this disease.

Efficacy of a commercial dry sleeve cryotherapy system for cooling the equine metacarpus.

OBJECTIVE: To determine the ability of a commercial cryotherapy system (Game Ready Equine) to cool the metacarpal subcutaneous tissue and the superficial digital flexor tendon (SDFT) in horses. STUDY DESIGN: Experimental study. ANIMALS OR SAMPLE POPULATION: Six healthy adult horses. METHODS: Thermocouples were implanted into the metacarpal subcutaneous tissues and the SDFT of six horses. Two treatments (cryotherapy or cryotherapy with 5-50 mmHg intermittent compression) were randomly assigned to forelimbs and performed for 20 minutes. Temperatures were compared to the target range of 10-19°C and between groups. RESULTS: Only one limb in the cryotherapy/compression group reached the target range after cryotherapy. Temperatures did not differ between treatment groups at time 0. Lowest temperatures achieved in the subcutaneous tissue (p = .0043) and SDFT (p = .005) were 4.9 and 7.6°C lower when intermittent compression was applied. Similarly, applying compression induced a maximum change in temperature of approximately 7.0°C in the subcutaneous tissue (p = .014) and 10.2°C in the SDFT (p = .0001). CONCLUSION: The cryotherapy system did not cool equine subcutaneous tissue or SDFT to the target temperature range, except in one limb. Combining cryotherapy with intermittent compression did result in lower temperatures and a greater change in temperature of the subcutaneous tissue and SDFT. CLINICAL SIGNIFICANCE: When using this cryotherapy system, the addition of intermittent compression should be considered to achieve lower temperatures and potentially greater reduction in inflammation. Further studies are warranted to determine the effect of longer treatment times, higher compression settings, and the optimal temperature for benefits in normal and diseased equine tissues.

Chronic Thrombocytopenia as the Initial Manifestation of STIM1-Related Disorders.

Pediatric thrombocytopenia has a wide differential diagnosis, and recently, genetic testing to identify its etiology has become more common. We present a case of a 16-year-old boy with a history of chronic moderate thrombocytopenia, who later developed constitutional symptoms and bilateral hand edema with cold exposure. Laboratory evaluation revealed evidence both of inflammation and elevated muscle enzymes. These abnormalities persisted over months. His thrombocytopenia was determined to be immune mediated. Imaging revealed lymphadenopathy and asplenia, and a muscle biopsy was consistent with tubular aggregate myopathy. Ophthalmology evaluation noted photosensitivity, pupillary miosis, and iris hypoplasia. Genetic testing demonstrated a pathogenic variant in STIM1 consistent with autosomal dominant Stormorken syndrome. Our case is novel because of the overlap of phenotypes ascribed to both gain-of-function and loss-of-function pathogenic variants in STIM1, thereby blurring the distinctions between these previously described syndromes. Pediatricians should consider checking muscle enzymes when patients present with thrombocytopenia and arthralgia, myalgia, and/or muscle weakness. Our case highlights the importance of both multidisciplinary care and genetic testing in cases of chronic unexplained thrombocytopenia. By understanding the underlying genetic mechanism to a patient's thrombocytopenia, providers are better equipped to make more precise medical management recommendations.

Isolated intracranial Whipple's disease--report of a rare case and review of the literature.

INTRODUCTION: Whipple's disease (WD) is a rare multisystemic infectious disease that can involve a variety of organs namely the gastrointestinal tract, lymphatic system, heart and nervous system. Myorhythmia is a hallmark of WD. Isolated CNS involvement is very rare. CASE: We present a 50 year-old African-American woman with rapid cognitive decline, visual hallucinations, insomnia, dysarthria, and gait unsteadiness. She subsequently developed pendular nystagmus and gaze paresis. Serial brain MRI scans showed T2 hyperintense lesions in the left striatum and right parahippocampal gyrus. FDG-PET scan showed marked increase of glucose uptake in the left putamen. Serum and CSF PCR for Tropheryma whipplei was negative. Stereotactic biopsy of the lesion and tissue PCR was consistent with WD. REVIEW OF LITERATURE: A systematic review identified 24 cases of isolated intracranial presentation of WD since 1975. Cases with systemic and extracranial manifestations were excluded. DISCUSSION: In patients with rapidly progressive cognitive decline with negative workup for common etiologies, there should be a high index of suspicion for WD. Diagnosis of WD remains a challenge as traditional methods commonly fail to culture T. whipplei. PET scans can help in identifying areas of inflammation that can be biopsied. Our case proves that a negative serum and CSF PCR should not exclude CNS WD and a brain biopsy of the lesion with PCR assay should be performed when possible.

Hepatic failure, neonatal hemochromatosis and porto-pulmonary hypertension in a newborn with trisomy 21--a case report.

Liver failure in neonates is a rare but often fatal disease. Trisomy 21 is not usually associated with significant infantile liver disease. If present, hepatic dysfunction in an infant with Trisomy 21 is likely to be attributed to transient myeloproliferative disorder with hepatic infiltration by hematopoietic elements and may be associated with secondary hemosiderosis. A less commonly recognized cause of liver failure in neonates with Trisomy 21 is neonatal hemochromatosis (NH); this association has been reported in nine cases of Trisomy 21 in literature. NH is a rare, severe liver disease of intra-uterine onset that is characterized by neonatal liver failure and hepatic and extrahepatic iron accumulation that spares the reticuloendothelial system. NH is the most frequently recognized cause of liver failure in neonates and the commonest indication for neonatal liver transplantation. Although porto-pulmonary hypertension (PPH) has been reported as a complication of liver failure in adults and older children, this has not been reported in neonates with liver failure of any etiology. This is probably due to the rarity of liver failure in newborns, delayed diagnosis and high mortality. The importance of recognizing PPH is that it is reversible with liver transplantation but at the same time increases the risk of post-operative mortality. Therefore, early diagnosis of PPH is critical so that early intervention can improve the chances of successful liver transplantation. We report for the first time the association of liver failure with porto-pulmonary hypertension secondary to NH in an infant with Trisomy 21.