A case of naltrexone-induced acute eosinophilic pneumonia.

Acute eosinophilic pneumonia (AEP) is a rare cause of acute respiratory failure. Clinical presentations can range from dyspnoea, fever and cough, to rapidly progressive and potentially fulminant respiratory failure. While its exact cause is often unknown, associations with inhalational injuries and exposures to new medications have been described.We report a case of a middle-aged, non-smoking man with a history of alcohol use disorder. He presented with 4 days of shortness of breath that started hours after taking injectable naltrexone (Vivitrol). The patient had rapidly worsening hypoxaemia, necessitating emergent bronchoscopy with transbronchial biopsies and bronchoalveolar lavage which showed 66% eosinophils. The patient was intubated for the procedure and unable to get extubated due to worsening hypoxaemic respiratory failure with high fractional inspired oxygen requirements. Chest radiograph showed worsening lung infiltrates and with a high index of suspicion for AEP, he was started empirically on methylprednisolone. He had rapid improvement in his respiratory status and was extubated on day 5 of admission then discharged on day 8. Histopathological examination confirmed acute/subacute eosinophilic pneumonia. A 3-week post-discharge follow-up chest radiograph confirmed the full resolution of pulmonary infiltrates.Naltrexone-induced AEP is rare, with only six other cases reported in the literature. Careful history taking and prompt evaluation for AEP are important given the potential for rapid progression to acute hypoxic respiratory failure and the excellent response to steroid treatment.

Prevalence of misdiagnosis of cellulitis: A systematic review and meta-analysis.

BACKGROUND: There is no gold standard test to accurately identify patients with cellulitis and therefore misdiagnosis is common. Using the clinical impression of a dermatology or an infectious disease specialist as a reference standard, we sought to determine the prevalence of misdiagnosis of cellulitis among nonspecialist physicians. METHODS: A systemic search was performed using MEDLINE, Cochrane Library, and EMBASE databases for studies reporting diagnostic accuracy of cellulitis. Inclusion criteria required dermatology or infectious disease consultation for all patients diagnosed with cellulitis by generalist physicians. We used random effects modeling to estimate the prevalence of misdiagnosis using consultant diagnosis as a reference standard. RESULTS: Eight studies contributed to the analysis. For the seven studies involving inpatients, the results were sufficiently homogeneous to justify pooling data. Of 858 inpatients initially diagnosed with cellulitis, 335 (39%, 95% confidence interval: 31-47) received an alternative diagnosis from the specialist. Heterogeneity was large (I2 = 74%) and the greatest contributor to between-study variance was the year of publication. Alternative diagnoses were mostly noninfectious (68%, 221/327), with stasis dermatitis (18%, 60/327) being the most common. An abscess was the most common alternative infectious diagnosis (10%, 32/327). DISCUSSION: Cellulitis is commonly misdiagnosed among inpatients, leading to unnecessary hospital admissions and antibiotic overuse. Most alternative diagnoses are noninfectious. Continuing medical education among general practitioners and urgent care providers will likely reduce cellulitis misdiagnoses.

Brachial plexopathy as a complication of COVID-19.

COVID-19 affects a wide spectrum of organ systems. We report a 52-year-old man with hypertension and newly diagnosed diabetes mellitus who presented with hypoxic respiratory failure due to COVID-19 and developed severe brachial plexopathy. He was not treated with prone positioning respiratory therapy. Associated with the flaccid, painfully numb left upper extremity was a livedoid, purpuric rash on his left hand and forearm consistent with COVID-19-induced microangiopathy. Neuroimaging and electrophysiological data were consistent with near diffuse left brachial plexitis with selective sparing of axillary, suprascapular and pectoral fascicles. Given his microangiopathic rash, elevated D-dimers and paucifascicular plexopathy, we postulate a patchy microvascular thrombotic plexopathy. Providers should be aware of this significant and potentially under-recognised neurologic complication of COVID-19.

How to understand and teach P values: a diagnostic test framework.

OBJECTIVES: The aim of the tutorial is to help educators address misconceptions about P values and provide a tool that can be used to teach a more contemporary interpretation. STUDY DESIGN AND SETTING: A scripted tutorial using problem-based learning and a diagnostic test analogy to deconstruct the misunderstandings about P values and develop a more Bayesian approach to study interpretation. RESULTS: A diagnostic test analogy is an effective teaching tool. Learners' understanding of Bayes' theorem in diagnostic testing can be used as a bridge to the realization that the prestudy probability of a true difference is crucial for study interpretation. The analogy has several caveats and shortcomings. The limitations of this analogy and the conceptual difficulties with the Bayesian study analyses are addressed. CONCLUSION: P values do not provide the information many assume they do-they are not equivalent to a probability of a chance finding. This tutorial helps move learners from these incorrect notions to new insights.

Increasing Incidence and Unique Clinical Characteristics of Spinning-Induced Rhabdomyolysis.

OBJECTIVE: To compare outcomes of spinning-induced rhabdomyolysis to those with exertional rhabdomyolysis from other physical activities. DESIGN: Retrospective cohort study. SETTING: Academic medical center, single-center. PATIENTS: A retrospective chart review was conducted on patients evaluated from December 2010 through November 2014. Patients were selected by ICD-9 code for rhabdomyolysis. Patients were included if the reason for admission was rhabdomyolysis caused by exertion. Cases of rhabdomyolysis caused by trauma or drugs were excluded. MAIN OUTCOME MEASURES: Muscle group involvement, admission, and peak creatine kinase levels, time from activity to hospitalization, length of hospital stay, and incidence of complications. RESULTS: Twenty-nine cases were reviewed with 14 admissions secondary to spinning. Median admission creatine kinase (73 000 IU/L vs 29 000 IU/L, P = 0.02) and peak creatine kinase levels were significantly higher in the spinning group (81 000 IU/L vs 31 000 IU/L, P = 0.007). Hospital admissions for spinning-induced rhabdomyolysis increased over time. CONCLUSION: Health care providers should be aware of the potential dangers of spinning-related rhabdomyolysis especially in otherwise healthy young people.

A protein sequence that can encode native structure by disfavoring alternate conformations.

The linear sequence of amino acids contains all the necessary information for a protein to fold into its unique three-dimensional structure. Native protein sequences are known to accomplish this by promoting the formation of stable, kinetically accessible structures. Here we describe a Pro residue in the center of the third transmembrane helix of the cystic fibrosis transmembrane conductance regulator that promotes folding by a distinct mechanism: disfavoring the formation of a misfolded structure. The generality of this mechanism is supported by genome-wide transmembrane sequence analyses. Furthermore, the results provide an explanation for the increased frequency of Pro residues in transmembrane alpha-helices. Incorporation by nature of such 'negative folding determinants', aimed at preventing the formation of off-pathway structures, represents an additional mechanism by which folding information is encoded within the evolved sequences of proteins.