Endogenous Serratia marcescens panophthalmitis: A case series.

PURPOSE: - Two rare and unusual cases of endogenous panophthalmitis from Serratia marcescens are presented with mechanisms for infection explored. Observations - The first patient had history of intravenous drug use (IVDU) without any medical implants. The second patient, in addition to IVDU, had a history of end-stage renal disease with upper extremity arteriovenous fistula graft infection from Serratia marcescens confirmed by wound culture. One patient had a history of licking the needles prior to IV drug injection. Clinical exam in both cases revealed light perception vision, relative afferent pupillary defect, periorbital edema with limited extraocular motility, and hypopyon in the affected eyes. Cultures from the anterior chamber aspirate were positive for Serratia marcescens in the first case and demonstrated Gram-negative rods in the second. Attempted vitreous aspiration was unsuccessful at obtaining specimens. Computed tomography demonstrated orbital fat stranding without abscess, and histopathology showed intense neutrophilic infiltration in all layers of enucleated specimen in case one. CONCLUSIONS AND IMPORTANCE: Needle licking may be an underappreciated mechanism for endogenous endophthalmitis in intravenous drug users. This report includes the first case in the literature, to authors' knowledge, of non-nosocomial endogenous Serratia marcescens panophthalmitis with orbital cellulitis. The second case illustrates a rare consequence of the rise in arteriovenous fistula placement and dialysis across the United States, which may predispose to future cases of endogenous Serratia marcescens endophthalmitis. This series supports previous observations of Serratia marcescens endogenous endophthalmitis exhibiting a generally poor visual prognosis.

Neuroepithelial Cyst of the Optic Nerve in a Newborn.

Cystic lesions of the optic nerve are uncommon findings that have been associated with neoplasms, systemic disorders, or described as idiopathic. They have been described in a wide range of ages, with few congenital cysts having been described in infants. Surgical excision of these lesions may lead to significant morbidity as previously reported cases often involved transection of the optic nerve. The authors describe a unique case of a newborn with a rare neuroepithelial cyst of the intraorbital optic nerve that was successfully excised while sparing the optic nerve, ultimately resulting in the resolution of an afferent pupillary defect. This case demonstrates that careful surgical excision of a benign optic nerve cyst can be performed without significant morbidity to potentially preserve vision.

Hybrid Neurofibroma/Schwannoma of the Supraorbital Nerve: Clinicopathologic Correlation of a Rare Tumor.

Benign peripheral nerve sheath tumors such as schwannoma and neurofibroma have long been considered distinct entities. Recently, hybrid tumors demonstrating combined morphological features of neurofibroma and schwannoma have been described, primarily in dermal locations. Only 1 case of hybrid peripheral nerve sheath tumor of the orbit has been reported in the literature. Hybrid morphology is important to recognize because of its association with the neurofibromatoses, including schwannomatosis; however, the paucity of literature on orbital hybrid peripheral nerve sheath tumor poses a diagnostic challenge. This article describes a case of hybrid neruofibroma/schwannoma of the orbit arising from the supraorbital nerve with clinicopathologic correlation.

Lethal neonatal meningoencephalitis caused by multi-drug resistant, highly virulent Escherichia coli.

Neonatal meningitis is a rare but devastating condition. Multi-drug resistant (MDR) bacteria represent a substantial global health risk. This study reports on an aggressive case of lethal neonatal meningitis due to a MDR Escherichia coli (serotype O75:H5:K1). Serotyping, MDR pattern and phylogenetic typing revealed that this strain is an emergent and highly virulent neonatal meningitis E. coli isolate. The isolate was resistant to both ampicillin and gentamicin; antibiotics currently used for empiric neonatal sepsis treatment. The strain was also positive for multiple virulence genes including K1 capsule, fimbrial adhesion fimH, siderophore receptors iroN, fyuA and iutA, secreted autotransporter toxin sat, membrane associated proteases ompA and ompT, type II polysaccharide synthesis genes (kpsMTII) and pathogenicity-associated island (PAI)-associated malX gene. The presence of highly-virulent MDR organisms isolated in neonates underscores the need to implement rapid drug resistance diagnostic methods and should prompt consideration of alternate empiric therapy in neonates with Gram negative meningitis.

Partial mGlu5 Negative Allosteric Modulators Attenuate Cocaine-Mediated Behaviors and Lack Psychotomimetic-Like Effects.

Cocaine abuse remains a public health concern for which pharmacotherapies are largely ineffective. Comorbidities between cocaine abuse, depression, and anxiety support the development of novel treatments targeting multiple symptom clusters. Selective negative allosteric modulators (NAMs) targeting the metabotropic glutamate receptor 5 (mGlu5) subtype are currently in clinical trials for the treatment of multiple neuropsychiatric disorders and have shown promise in preclinical models of substance abuse. However, complete blockade or inverse agonist activity by some full mGlu5 NAM chemotypes demonstrated adverse effects, including psychosis in humans and psychotomimetic-like effects in animals, suggesting a narrow therapeutic window. Development of partial mGlu5 NAMs, characterized by their submaximal but saturable levels of blockade, may represent a novel approach to broaden the therapeutic window. To understand potential therapeutic vs adverse effects in preclinical behavioral assays, we examined the partial mGlu5 NAMs, M-5MPEP and Br-5MPEPy, in comparison with the full mGlu5 NAM MTEP across models of addiction and psychotomimetic-like activity. M-5MPEP, Br-5MPEPy, and MTEP dose-dependently decreased cocaine self-administration and attenuated the discriminative stimulus effects of cocaine. M-5MPEP and Br-5MPEPy also demonstrated antidepressant- and anxiolytic-like activity. Dose-dependent effects of partial and full mGlu5 NAMs in these assays corresponded with increasing in vivo mGlu5 occupancy, demonstrating an orderly occupancy-to-efficacy relationship. PCP-induced hyperlocomotion was potentiated by MTEP, but not by M-5MPEP and Br-5MPEPy. Further, MTEP, but not M-5MPEP, potentiated the discriminative-stimulus effects of PCP. The present data suggest that partial mGlu5 NAM activity is sufficient to produce therapeutic effects similar to full mGlu5 NAMs, but with a broader therapeutic index.

Papillary tumor of the pineal region with synchronous suprasellar focus and novel cytogenetic features.

Papillary tumor of the pineal region (PTPR) is an uncommon neoplasm with variable biologic behavior. Cytogenetic and molecular diagnostic studies are rare, yielding no definitive genetic signature. We report a case of PTPR with a multicentric presentation and unusual cytogenetic features. A 25-year-old man presented with headache, disconjugate gaze, and confusion. Mass lesions in the pineal and suprasellar regions, with identical imaging characteristics, were identified. The former extended partially into the fourth ventricle. It showed typical PTPR histology and losses of chromosomes 3, 7, 10, 14, 18, and Y with gains of chromosomes 3, 8, and 9. Seventeen months postsurgery, the patient is stable without disease progression after radiation therapy. Synchronous mass lesions at presentation and losses of chromosomes 3, 7, 14, 18, and Y are unusual features, adding to the available data and underscoring the biologic and genetic variability associated with these neoplasms.