Seronegative Atypical Anti-Glomerular Basement Membrane Glomerulonephritis Associated With Thrombotic Microangiopathy: Case Report and Literature Analysis.

Anti-glomerular basement membrane (GBM) antibody nephritis is defined by linear immunofluorescence staining of GBM by immunoglobulin G (IgG), typically associated with GBM rupture, fibrinoid necrosis, and crescent formation. Clinically, the patients present with rapidly worsening renal function, often with hematuria. Typical renal pathologic findings include necrotizing and crescentic glomerulonephritis. In contrast, thrombotic microangiopathy (TMA) is characterized by microvascular thrombosis, which can also lead to acute kidney injury. Thrombotic microangiopathy is associated with some systemic diseases and has characteristic clinical features of microangiopathic hemolytic anemia, platelet consumption, and multiple organ failure. Anti-GBM nephritis associated with TMA has rarely been reported. We describe an unusual case of atypical anti-GBM disease without crescent formation or necrosis but with light microscopic and ultrastructural features consistent with endothelial cell injury and glomerular-limited TMA.

An Uncommon Presentation of Vasopressin-Induced Purpura Fulminans.

Purpura fulminans (PF) is a rarely encountered rapidly evolving dermatological manifestation of ischemia, particularly in critically ill patients. Considered one of the very few dermatological emergencies, it has high mortality rate where patients often succumb to the illness. It can manifest in three forms: neonatal, idiopathic, and the more commonly infectious variety, which can be secondary to mostly bacterial and rarely viral etiology. It is also reported to be highly associated with disseminated intravascular coagulation (DIC), heparin-induced thrombocytopenia (HIT), and acute hepatic failure (AHF). Hereditary or acquired deficiency of protein C and dysregulation of the coagulation cascade, mainly protein C-thrombomodulin, has been implicated in the pathogenesis. We present a 55-year-old male admitted to the intensive care unit for diabetic ketoacidosis (DKA) and septic shock. Along with initiating management protocol for DKA and broad-spectrum antibiotics, he was initially started on norepinephrine for septic shock. Because of persistent refractory septic shock, he was subsequently initiated on phenylephrine and vasopressin to maintain adequate perfusion. The following day, he was found to have sharply demarcated blackish non-blanching discoloration on bilateral knees, lower limbs, and scrotum, sparing the acral regions. This cutaneous manifestation persisted throughout his hospital course, although it improved after discontinuation of vasopressin while continuing with other pressors. Vasopressin has been implicated in a few instances of skin necrosis; however, PF has rarely been documented and never within 1 day like ours. This case demonstrates a unique development of PF likely from vasopressin after ruling out the diagnoses of DIC, HIT, thrombotic thrombocytopenic purpura, and AHF.

Predictors of voice therapy efficacy in vocal cord dysfunction at a tertiary care center.

OBJECTIVE: Vocal cord dysfunction is inappropriate adduction of vocal cords during inspiration that causes dyspnea and is commonly mistaken for exercise-induced asthma. To improve diagnostic accuracy, this study aims to identify demographics associated with vocal cord dysfunction and to determine their impact on the efficacy of voice therapy in improving vocal cord function. STUDY DESIGN: Retrospective chart review. SETTING: Single tertiary care institution between January 2015 and December 2021. METHODS: 184 patients who underwent voice therapy for vocal cord dysfunction were included. The primary outcome was patient self-reported percent improvement of symptoms. The secondary outcome was number of voice therapy treatments. RESULTS: The mean duration of symptoms was 2 ± 3 years. The mean number of voice therapy treatments was 2.2 ± 1.5. Of the 107 (58.2 %) patients with documented perceived breathing improvement percentages recorded, the mean maximal percent improvement was 72.5 ± 21.5 %. Mean maximal percent improvement of symptoms increased with each voice therapy treatment (p = 0.01). This association remained significant when controlling for comorbid conditions such as allergic rhinitis with postnasal drip, anxiety, asthma, and gastroesophageal reflux disease in multivariate analysis (p = 0.005). Patients with asthma had significantly higher maximum percent breathing improvement compared to those without asthma (p = 0.026). Similarly, patients who played sports had significantly higher maximum percent breathing improvement compared to those who did not (p = 0.022). CONCLUSION: Patient perceived breathing improvement with voice therapy is higher among those with concomitant asthma and those who play sports. Voice therapy is a safe and effective first line treatment of vocal cord dysfunction even when controlling for comorbid conditions.

Cc2d1b Contributes to the Regulation of Developmental Myelination in the Central Nervous System.

Background: Numerous studies have indicated that myelination is the result of the interplay between extracellular signals and an intricate network of transcription factors. Yet, the identification and characterization of the full repertoire of transcription factors that modulate myelination are still incomplete. CC2D1B is a member of the Lgd/CC2D1 family of proteins highly expressed in myelinating cells in the central and peripheral nervous systems. In addition, the absence of CC2D1B limits myelin formation in vitro. Here we propose to delineate the function of CC2D1B in myelinating cells during developmental myelination in vivo in the central and peripheral nervous systems. Methods: We used a Cc2d1b constitutive knockout mouse model and then performed morphological analyses on semithin sections of sciatic nerves and electron micrographs of optic nerves. We also performed immunohistological studies on coronal brain sections. All analyses were performed at 30 days of age. Results: In the peripheral nervous system, animals ablated for Cc2d1b did not show any myelin thickness difference compared to control animals. In the central nervous system, immunohistological studies did not show any difference in the number of oligodendrocytes or the level of myelin proteins in the cortex, corpus callosum, and striatum. However, optic nerves showed a hypomyelination (0.844 ± 0.022) compared to control animals (0.832 ± 0.016) of large diameter myelinated fibers. Conclusions: We found that CC2D1B plays a role in developmental myelination in the central nervous system. These results suggest that CC2D1B could contribute to gene regulation during oligodendrocytes myelination in optic nerves.