Tomoko Tsukamoto

Predictors for benign paroxysmal positional vertigo with positive Dix–Hallpike test

Objective Patient medical history is important for making a diagnosis of causes of dizziness, but there have been no studies on the diagnostic value of individual items in the history. This study was performed to identify and validate useful questions for suspecting a diagnosis of benign paroxysmal positional vertigo (BPPV). Methods Construction and validation of a disease prediction model was performed at the outpatient clinic in the Department of General Medicine of Chiba University Hospital. Patients with dizziness were enrolled (145 patients for construction of the disease prediction model and 61 patients for its validation). This study targeted BPPV of the posterior semicircular canals only with a positive Dix–Hallpike test (DHT + BPPV) to avoid diagnostic ambiguity. Binomial logistic regression analysis was performed to identify the items that were useful for diagnosis or exclusion of DHT + BPPV. Results Twelve patients from the derivation set and six patients from the validation set had DHT + BPPV. Binomial logistic regression analysis selected a “duration of dizziness ≤15 seconds” and “onset when turning over in bed” as independent predictors of DHT + BPPV with an odds ratio (95% confidence interval) of 4.36 (1.18–16.19) and 10.17 (2.49–41.63), respectively. Affirmative answers to both questions yielded a likelihood ratio of 6.81 (5.11–9.10) for diagnosis of DHT + BPPV, while negative answers to both had a likelihood ratio of 0.19 (0.08–0.47). Conclusion A “duration of dizziness ≤15 seconds” and “onset when turning over in bed” were the two most important questions among various historical features of BPPV.

Paroxysmal hip pain.

In January, 2007, a 58-year-old woman presented to our department with a 2-year history of severe paroxysmal hip pain. She had a 30-year history of anorexia nervosa. The pain originated near the pubis and radiated to the right or left hip, with right-sided pain being more frequent. The pain often occurred after urination or defecation, and lasted from several minutes to several hours. She could not walk because of the severity of the pain, and had to lie supine with the aff ected thigh fl exed to obtain some relief. Our patient had presented to emergency departments several times, receiving a diagnosis of psychogenic pain or osteoarthritis because of degenerative changes shown on hip radiographs. On examination, she was asymptomatic but severely emaciated with a height of 159 cm and weight of 32 kg (body-mass index 12·7 kg/m2). There was no tenderness, swelling, or restricted movement of her hip joints, making the diagnosis of degenerative arthritis unlikely. Just after examination, left-sided pain occurred on urination. Emergency CT of the pelvis showed intrusion of the bowel into the left obturator canal (fi gure). Her pain soon subsided, and elective surgery was scheduled. After 1 month, severe right-sided pain occurred and she had an emergency laparotomy. Bilateral obturator hernia was diagnosed and mesh repair surgery done. In August, 2009, at 32-month follow-up she had not experienced any pain since the operation. Obturator hernia is most common in emaciated elderly women between 70 and 90 years old. Women are aff ected six times more frequently than men because they have a wider pelvis with a larger obturator canal. Emaciation is an important risk factor because the loss of preperitoneal fat overlying the obturator canal increases the risk of herniation. Obturator hernia is relatively rare, with a reported incidence of 0·073% of all abdominal hernias and bilateral obturator hernia has an incidence of only 0·013%. The hernia is more common in multiparous women and Asians, and occurs less frequently on the left side because the sigmoid colon can cover the left obturator foramen, preventing herniation. The usual presention is with the clinical features of acute small bowel obstruction, but obstruction can also be partial and resolve spontaneously. Approximately one third of the patients have a history of intermittent previous attacks. Patients can present with groin, thigh, knee, or hip pain due to compression of the obturator nerve by the hernia (Howship-Romberg sign), which is seen in 15–50% of patients. The pain is exacerbated by extension, abduction, or medial rotation of the thigh, while fl exion usually relieves it. Our patient with bilateral hernia was relatively young, but she had severe emaciation due to anorexia nervosa. Bowel herniation induced the HowshipRomberg sign, resulting in her curious paroxysmal hip pain. Diagnosis of obturator hernia is challenging, although CT or ultrasonography can be useful, the correct diagnosis is made preoperatively in only 21·5% to 31·3% of cases. Diffi culty in establishing the diagnosis leads to a high mortality rate of up to 25%, so early accurate diagnosis is crucial. Although obturator hernia is a rare disease, it must be considered when any underweight woman, not only the elderly, complains of unexplained pain in the groin, thigh, knee, or hip.

Influence of predicting the diagnosis from history on the accuracy of physical examination

Background This study aimed to clarify the influence of predicting a correct diagnosis from the history on physical examination by comparing the diagnostic accuracy of auscultation with and without clinical information. Methods The participants were 102 medical students from the 2013 clinical clerkship course. Auscultation was performed with a cardiology patient simulator. Participants were randomly assigned to two groups. Each group listened to a different simulated heart murmur and then made a diagnosis without clinical information. Next, a history suggesting a different murmur was provided to each group and they predicted the diagnosis. Finally, the students listened to a murmur corresponding to the history provided and again made a diagnosis. Correct and incorrect diagnosis rates of auscultation were compared between students with and without clinical information, between students predicting a correct or incorrect diagnosis from the history (correct and incorrect prediction groups, respectively), and between students without clinical information and those making an incorrect prediction. Results For auscultation with or without clinical information, the correct diagnosis rate was 62.7% (128/204 participants) versus 54.4% (111/204 participants), showing no significant difference (P=0.09). After receiving clinical information, a correct diagnosis was made by 102/117 students (87.2%) in the correct prediction group versus 26/87 students (29.9%) in the incorrect prediction group, showing a significant difference (P=0.006). The correct diagnosis rate was also significantly lower in the incorrect prediction group than when the students performed auscultation without clinical information (54.4% versus 29.9%, P<0.001). Conclusion Obtaining a history alone does not improve the diagnostic accuracy of physical examination. However, accurately predicting the diagnosis from the history is associated with higher diagnostic accuracy of physical examination, while incorrect prediction is associated with lower diagnostic accuracy of examination.

Prolonged Dry Cough without Pulmonary Changes on Radiological Imaging

A 16-year-old boy who was a non-smoker presented with a prolonged severe dry cough and malaise of 3 months in duration. Despite an increase in the patients inflammatory marker levels, no respiratory lesions were radiologically or serologically detected. We suspected that the cough reflex pathway had been stimulated by large vessel vasculitis (LVV, a non-respiratory inflammatory condition) and diagnosed the patient with Takayasu arteritis. While inflammation of either the ascending pharyngeal or pulmonary artery have been reported to cause cough in patients with LVV, the present case shows that intense inflammation of the aortic arch and the starting portion of its main branches may stimulate a vagus nerve branch as a novel mechanism causing cough.

Iliac Vein Compression Syndrome due to Bladder Distention Caused by Urethral Calculi.

We report a rare case of iliac vein compression syndrome caused by urethral calculus. A 71-year-old man had a history of urethral stenosis. He complained of bilateral leg edema and dysuria for 1 week. Physical examination revealed bilateral distention of the superficial epigastric veins, so obstruction of both common iliac veins or the inferior vena cava was suspected. Plain abdominal computed tomography showed a calculus in the pendulous urethra, distention of the bladder (as well as the right renal pelvis and ureter), and compression of the bilateral common iliac veins by the distended bladder. Iliac vein compression syndrome was diagnosed. Bilateral iliac vein compression due to bladder distention (secondary to neurogenic bladder, benign prostatic hyperplasia, or urethral calculus as in this case) is an infrequent cause of acute bilateral leg edema. Detecting distention of the superficial epigastric veins provides a clue for diagnosis of this syndrome.

Accuracy of diagnoses predicted from a simple patient questionnaire stratified by the duration of general ambulatory training: an observational study.

Purpose To compare the diagnostic accuracy of diseases predicted from patient responses to a simple questionnaire completed prior to examination by doctors with different levels of ambulatory training in general medicine. Participants and methods Before patient examination, five trained physicians, four short-term-trained residents, and four untrained residents examined patient responses to a simple questionnaire and then indicated, in rank order according to their subjective confidence level, the diseases they predicted. Final diagnosis was subsequently determined from hospital records by mentor physicians 3 months after the first patient visit. Predicted diseases and final diagnoses were codified using the International Classification of Diseases version 10. A “correct” diagnosis was one where the predicted disease matched the final diagnosis code. Results A total of 148 patient questionnaires were evaluated. The Herfindahl index was 0.024, indicating a high degree of diversity in final diagnoses. The proportion of correct diagnoses was high in the trained group (96 of 148, 65%; residual analysis, 4.4) and low in the untrained group (56 of 148, 38%; residual analysis, −3.6) (χ2=22.27, P<0.001). In cases of correct diagnosis, the cumulative number of correct diagnoses showed almost no improvement, even when doctors in the three groups predicted ≥4 diseases. Conclusion Doctors who completed ambulatory training in general medicine while treating a diverse range of diseases accurately predicted diagnosis in 65% of cases from limited written information provided by a simple patient questionnaire, which proved useful for diagnosis. The study also suggests that up to three differential diagnoses are appropriate for diagnostic prediction, while ≥4 differential diagnoses barely improved the diagnostic accuracy, regardless of doctors’ competence in general medicine. If doctors can become able to predict the final diagnosis from limited information, the correct diagnostic outcome may improve and save further consultation hours.