Description and evaluation of the vallecula sign: a new radiologic sign in the diagnosis of adult epiglottitis

Using Transfer Learning of Convolutional Neural Network on Neck Radiographs to Identify Acute Epiglottitis

Acute epiglottitis (AE) is a life-threatening condition and needs to be recognized timely. Diagnosis of AE with a lateral neck radiograph yields poor reliability and sensitivity. Convolutional neural networks (CNN) are powerful tools to assist the analysis of medical images. This study aimed to develop an artificial intelligence model using CNN-based transfer learning to identify AE in lateral neck radiographs. All cases in this study are from two hospitals, a medical center, and a local teaching hospital in Taiwan. In this retrospective study, we collected 251 lateral neck radiographs of patients with AE and 936 individuals without AE. Neck radiographs obtained from patients without and with AE were used as the input for model transfer learning in a pre-trained CNN including Inception V3, Densenet201, Resnet101, VGG19, and Inception V2 to select the optimal model. We used five-fold cross-validation to estimate the performance of the selected model. The confusion matrix of the final model was analyzed. We found that Inception V3 yielded the best results as the optimal model among all pre-train models. Based on the average value of the fivefold cross-validation, the confusion metrics were obtained: accuracy = 0.92, precision = 0.94, recall = 0.90, and area under the curve (AUC) = 0.96. Using the Inception V3-based model can provide an excellent performance to identify AE based on radiographic images. We suggest using the CNN-based model which can offer a non-invasive, accurate, and fast diagnostic method for AE in the future.

Double thumb sign in a case of epiglottitis

Epiglottitis is a potentially life-threatening condition that requires quick and accurate diagnoses. The gold standard for diagnosis is for laryngoscopic visualisation of the epiglottis. However, this may not be well-tolerated in a patient with impending airway collapse, and lateral neck radiographs may support the diagnosis. The thumb sign is a recognized radiological feature of epiglottitis. We present a case of a 57-year-old gentleman with epiglottitis, whose lateral neck radiograph had the interesting feature of a double thumb sign. In spite of the significant airway oedema, he was conservatively managed with subsequent full recovery. The objective of this case report is to highlight the severity of airway narrowing with this radiological finding of double thumb sign, to alert the clinician to have closer monitoring or to consider artificial airway support.

Influenza A-Associated Epiglottitis and Compensatory Pursed Lip Breathing in an Infant

The last 3 decades have seen a shift in the epidemiology of epiglottitis. Epiglottitis was once most commonly associated with Haemophilus influenzae type B. However, with the implementation of the H. influenzae type B vaccine in 1985, the incidence has drastically declined. There are now new emerging pathogens-bacteria, viruses, and fungi-causing epiglottitis. Here, we report the first case of epiglottitis secondary to influenza A in a former full-term, vaccinated infant who presented with cough, fever, stridor, pursed lip breathing, and progressive respiratory distress and eventual respiratory failure. This case highlights the presentation and clinical course of epiglottitis and describes a rare clinical feature, pursed lip breathing, in an infant.

Clinical Mimics: An Emergency Medicine-Focused Review of Streptococcal Pharyngitis Mimics

BACKGROUND

Pharyngitis is a common disease in the emergency department (ED). Despite a relatively low incidence of complications, there are many dangerous conditions that can mimic this disease and are essential for the emergency physician to consider.

OBJECTIVE

This article provides a review of the evaluation and management of group A β-hemolytic Streptococcal (GABHS) pharyngitis, as well as important medical conditions that can mimic this disease.

DISCUSSION

GABHS pharyngitis often presents with fever, sore throat, tonsillar exudates, and anterior cervical lymphadenopathy. History and physical examination are insufficient for the diagnosis. The Centor criteria or McIsaac score can help risk stratify patients for subsequent testing or treatment. Antibiotics may reduce symptom duration and suppurative complications, but the effect is small. Rheumatic fever is uncommon in developed countries, and shared decision making is recommended if antibiotics are used for this indication. Oral analgesics and topical anesthetics are important for symptom management. Physicians should consider alternate diagnoses that may mimic GABHS pharyngitis, which can include epiglottitis, infectious mononucleosis, Kawasaki disease, acute retroviral syndrome, Lemierre's syndrome, Ludwig's angina, peritonsillar abscess, retropharyngeal abscess, and viral pharyngitis. A focused history and physical examination can help differentiate these conditions.

CONCLUSIONS

GABHS may present similarly to other benign and potentially deadly diseases. Diagnosis and treatment of pharyngitis should be based on clinical evaluation. Consideration of pharyngitis mimics is important in the evaluation and management of ED patients.

Adult Acute Epiglottitis: Predictors for Airway Intervention and Intensive Care Unit Admission

Objectives

(1) to characterise the clinical features of acute epiglottitis in adults in Hong Kong; (2) to identify predictors for airway intervention and uneventful recovery without intensive care unit (ICU) admission. Modified Early Warning Score (MEWS) was also applied in risk stratification.

Methods

A retrospective cohort study of 122 consecutive laryngoscopically confirmed cases admitted to Pamela Youde Nethersole Eastern Hospital from 1998 to 2007.

Results

The mean patient age was 51 years (range 18–84 years) and the male-to-female ratio was 1.9 to 1. Sore throat, dysphagia and odynophagia were the commonest symptoms and the median MEWS on presentation was 1 (range 0–10). Nine patients (7.4%) required airway intervention (5 orotracheal intubations, 2 nasotracheal intubations and 2 tracheostomies) and one patient died. Univariate analysis showed that recurrent attack (OR 35.0, 95% CI 2.77–442.69, p=0.013), dyspnoea (OR 17.41, 95%CI 2.09–144.79, p=0.001), stridor (OR 30.0, 95%CI 2.42–372.65, p=0.016) and MEWS equal to or greater than 4 (OR 5.81. 95%CI 1.16–29.17, p=0.049) were significantly associated with airway intervention. Only stridor remained a reliable predictor in multivariate analysis (OR 88.46, 95%CI 5.48–1427.45, p=0.001). Performance of MEWS in prediction for airway intervention was evaluated with the Receiver Operating Characteristic (ROC) curve. The area under curve (AUC) was 0.71 (95%CI 0.503–0.909). Forty-five patients did not require ICU admission (36.9%). Multiple logistic regression showed that absence of hoarseness (OR 3.10, 95%CI 1.10–8.79, p=0.033), absence of fever (OR 3.2, 95%CI 1.25–8.16, p=0.015) and MEWS <1 (OR 7.07, 95%CI 1.31–38.07, p=0.023) were predictors of uneventful recovery without ICU care.

Conclusion

A selective approach should be adopted in airway management but those with stridor on presentation should have their airway secured without delay. MEWS cannot replace clinical judgement but a low MEWS on presentation may help in identifying low risk patients who can be managed safely without ICU admission.

Case and Literature Review: Adult Acute Epiglottitis – Rising Incidence or Increasing Awareness?

Objective

The prevalence of adult acute epiglottitis is probably more common than is generally appreciated. A retrospective case review in a district hospital and a medical literature search may provide baseline information to guide future strategies.

Methods

Cases of acute epiglottitis in a period of 3 years and 4 months were traced from the hospital computer systems. Medical records were reviewed. Medical literature on “adult acute epiglottitis” was searched through Medline and EMBASE. Relevant full text articles were retrieved through hospital library network.

Results

From February 1998 to June 2001, 11 cases of acute epiglottitis were identified. The age range was 34–78 (mean 47.5, median 41). There was no paediatric case. The male to female ratio was 9:2. Eight presented with fever, sore throat and dysphagia, one presented with dyspnoea and two presented as foreign body in throat. Nine were treated successfully conservatively. Two were intubated prophylactically. There was no case fatality.

Conclusion

Adult acute epiglottitis has become much commoner than its paediatric counterpart. Acute epiglottitis should be suspected in all patients with a sore throat and dysphagia, especially if symptoms are out of proportion to the pharyngeal inflammation.

Diagnostic accuracy of radiographs for detecting supraglottitis: a systematic review and meta-analysis

Aim

To assess the diagnostic performance of lateral radiograph of the neck for supraglottitis in adults and children.

Methods

Electronic database searches (including PubMed, EMBASE, CINAHL, Web of Science, and WHO International Clinical Trials Registry Platform) were carried out through July 2014. Citations of included studies and recent narrative reviews were searched. Studies that compared lateral radiograph of the neck with a reference standard of direct/indirect laryngoscopy were included. Two reviewers independently assessed the methodological quality of included studies by Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2).

Results

Of 2,088 potentially relevant citations, two single-gate (cohort) studies and six two-gate (case-control) studies were identified. These included studies of design are at the moderate or high risk of bias in QUADAS-2. The pooled sensitivity from bivariate random-effects regression was 92.9% (95% confidence interval [CI], 88.5-95.9%) and the pooled specificity was 89.2% (95% CI, 85.9-91.9%), but the diagnostic value would be overestimated because of selection bias in the six two-gate studies. The sensitivity and specificity of the single-gate studies were 100.0% (95% CI, 92.2-100.0%) and 30.6% (95% CI, 15.5-35.6%) in children and 81.0% (95% CI, 78.2-93.2%) and 85.7% specificity (95% CI, 78.2-93.2%) in adults.

Conclusion

This study determines that there are insufficient studies of lateral neck radiograph for detecting supraglottitis. Lateral radiograph of the neck seems to have moderate accuracy for detecting supraglottitis. Further approximately unbiased studies are needed to obtain more valid and reliable estimates of test accuracy.

Schematic interpretation of lateral neck radiographs of adults in the emergency department: a pictorial review

The lateral neck radiograph is widely utilized for the evaluation of common neck conditions in the emergency department. The anatomy of the neck is complex and it can be difficult to differentiate between soft tissue structures on a lateral radiograph. We suggest a schematic pattern of interpreting the lateral neck radiograph with case images of various pathologies that can present in the emergency setting.

Diagnostic accuracy of lateral neck radiography in ruling out supraglottitis: a prospective observational study

OBJECTIVE

To assess the diagnostic accuracy of lateral neck radiographs (LNR) for acute supraglottitis in adults.

DESIGN

A single centre prospective observational study.

SETTING

Emergency department at Kurashiki Central Hospital, Japan.

PARTICIPANTS

Adult patients who underwent LNR to detect supraglottitis.

MAIN OUTCOME MEASURES

Presence of supraglottitis, based on nasopharyngeal laryngoscopy or a follow-up telephone call, 7-30 days after the visit.

RESULTS

140 patients had LNR during the study period. 35 patients were excluded from further analysis because of lack of consent. Of the 105 eligible patients, 21 patients (20%) were given the diagnosis of supraglottitis: 17 of 29 with a radiographic abnormality, and 4 of 76 patients without a radiographic abnormality. Three of the four cases where LNR was negative was grade 1, and all cases of grade 3 or higher had abnormal LNR. Sensitivity and specificity (95% CI) of LNR for supraglottitis were 81.0% (64.2 to 97.7) and 85.7% (78.2 to 93.2), respectively. The positive predictive value of LNR was 58.6% (40.7 to 76.5) and the negative predictive value was 94.7% (89.7 to 99.8). The positive likelihood ratio of LNR was 5.67 (3.27 to 9.82) and the negative likelihood ratio was 0.22 (0.10 to 0.51).

CONCLUSIONS

LNR showed only moderate sensitivity and specificity for supraglottitis and would miss some cases of supraglottitis if the pre-test probability is high. LNR was very sensitive for grade 3 or higher supraglottitis, but would miss milder cases.

TRIAL REGISTRATION

UMIN000011928.

Acute airway obstruction, an unusual presentation of vallecular cyst

A 18-year-old female presented to us with acute respiratory obstruction, unconsciousness, severe respiratory acidosis, and impending cardiac arrest. The emergency measures to secure the airway included intubation with a 3.5-mm endotracheal tube and railroading of a 6.5-mm endotracheal tube over a suction catheter. Video laryngoscopy done after successful resuscitation showed an inflamed swollen epiglottis with a swelling in the left vallecular region, which proved to be a vallecular cyst. Marsupialisation surgery was performed on the 8^th post admission day and the patient discharged on 10^th day without any neurological deficit.

Acute supraglottitis in adults

OBJECTIVES

Adult supraglottitis is a potentially life-threatening airway infection. We reviewed the management and outcome of supraglottitis in 169 adults admitted to Liverpool Hospital between 1999 and 2009.

METHODS

A retrospective review was conducted of all admissions with supraglottitis in patients at least 18 years of age. The diagnosis was confirmed by fiberoptic nasolaryngoscopy or direct laryngoscopy under general anesthesia. The main outcome measure was the need for intubation or tracheotomy. Univariate analysis was performed to determine factors that led to a worse outcome.

RESULTS

There were 80 men and 89 women in the cohort, with a median age of 51 years. Of these, 140 patients were admitted to the intensive care unit for a mean duration of 2 days. The common symptoms and signs at presentation were odynophagia and dysphagia (94%), dysphonia (65%), and stridor (33%). Endotracheal intubation was performed in 16 patients, and an awake tracheotomy was required in 4 patients. Dexamethasone acetate was used in 103 patients. Thirty-five patients had diabetes mellitus as a comorbidity. The presence of diabetes was predictive of the need for intubation or tracheotomy (p < 0.05), and the use of steroids was predictive of an intensive care unit stay of 24 hours or less (p < 0.05).

CONCLUSIONS

Fiberoptic laryngoscopy is the gold standard for diagnosis of supraglottitis, and close airway monitoring is crucial. Conservative management of the airway is a viable option, but the presence of diabetes makes airway intervention more likely. The use of steroids aids in symptom alleviation and hastens resolution of airway swelling, with no negative sequelae.

Aspergillus epiglottitis in a non-immunocompromised patient

The authors present a case that highlights an atypical example of a fungal epiglottis in an otherwise well adult patient with no medical history of fungal infection or an immunocompromised state. As current medical literature presents this fungus as only manifesting in the immunocompromised, the authors suggest, by this case report, that fungal pathogens be considered as a potential cause of epiglottitis in non-immunocompromised patients.

Identifying acute epiglottitis in adults. High degree of awareness, close monitoring are key

Epiglottitis can be a rapidly fatal condition in adults. Important clues that should raise clinical suspicion include the tripod sign, fever, stridor, sore throat, odynophagia, shortness of breath, and drooling. These features must be differentiated from those associated with common viral infections. The most helpful diagnostic studies are radiography of the neck and direct laryngoscopy. The patient's airway should be monitored during evaluation to avoid obstruction. Successful management requires teamwork between the primary care physician and personnel skilled in intubation as well as timely consultation with an otolaryngologist. Laryngoscopy and intubation always should be performed by the most skilled personnel because repeated attempts may increase periepiglottal swelling and the risk of airway obstruction. Racemic epinephrine should be avoided because of the rebound effect. Awareness of the possibility of epiglottitis in adults and close monitoring of the airway are the keys to management of this potentially life-threatening condition.

Adult epiglottitis: an under-recognized, life-threatening condition

Epiglottitis in the adult can be fatal and should be treated with the same degree of concern and suspicion in respect of airway patency as in children. We present three cases of adult epiglottitis in which the airway was lost prior to or during the intervention of an anaesthetist. We suggest that an emphasis on conservative management is distracting and belies the serious nature of this disease.