Frequent Alternative Diagnoses Research Articles

Diagnostic delay in Hidradenitis suppurativa investigated using data from social media and from statutory health insurances.

The chronic inflammatory skin disease hidradenitis suppurativa (HS) leads to severe pain and reduced quality of life. Nonetheless, it often takes years until a correct diagnosis is made. In this analysis, disease-related experiences and pathways of patients with HS were investigated and compared with the physicians' perspective. Public posts on forums and social media as well as results of a survey conducted among dermatologists and their patients on the actual medical care reality of HS in Germany were analysed. Furthermore, claims data from German health insurance companies were evaluated. Patients with HS suffer from a 43.3% reduction in working ability. Dermatology (26.5%) was the most frequently consulted specialty, with HS diagnosed predominantly in the inpatient setting (43.8%). Abscesses were described as the most frequent alternative diagnosis in HS patients (53.2%). Patient-reported changes of physicians in dermatology (34.1%) and surgery (42.4%) occurred predominantly within the specialty. Dermatology received most referrals from general practitioners (67.1%), but only 12.1% from surgeons. There is an urgent need to reduce the delay in diagnosis and the prolonged burden of disease in patients with HS. Therefore, awareness of the disease, its detection and treatment which goes beyond dermatology should be promoted, if possible as part of medical studies.

Subnormal visual acuity after compliant amblyopia therapy: residual/refractory amblyopia or co-existing pathology? - a retrospective analysis

ABSTRACT Purpose: To assess the prevalence of alternate etiology/co-existing pathology among patients with amblyopia, and to characterize factors contributing to over-diagnosis of amblyopia. Methods: We retrospectively reviewed records of children (from 1 January 2016 to 31 December 2019) who were initially diagnosed as “amblyopia” but later an alternate diagnosis for subnormal vision was established. Patients who had a best corrected visual acuity (BCVA) of ≤20/32 (0.2 logMAR) after compliant amblyopia therapy were divided into 2 groups: those with refractory amblyopia (BCVA improvement from baseline <1 logMAR line) and residual amblyopia (BCVA improvement from baseline >1 logMAR line). Data was collected for presence/absence of amblyogenic risk factors, history, ocular examination, and investigations leading to the final alternate diagnosis. We analyzed the factors that contributed to the initial over-diagnosis of amblyopia using the diagnostic error evaluation and research (DEER) taxonomy tool. Results: During the study period, 508 children with an initial diagnosis of amblyopia met the study criteria. Among these 508 children, 466 were diagnosed to have amblyopia alone, while 26 children (5.1%, median age: 7 years, 17 boys: 9 girls) were revised to have an alternate diagnosis/co-existing pathology. These 26 patients comprised of 2 groups: children referred to us as amblyopia but rediagnosed to have an alternate diagnosis; and a second subset, initially diagnosed by us to have amblyopia, but later found to have alternate diagnosis/co-existing pathology. Subclinical optic neuritis (50%, 13 children), and occult macular dystrophy (OMD) (38.4%, 10 children) were the most frequent alternative diagnoses. Children with ametropic amblyopia (8/26, 30.7%) were most frequently misdiagnosed. Risk factors that led to an initial diagnosis of amblyopia were: high refractive error and heterotropia in 7 patients each (26.9%), anisometropia in 12 (46.1%), and prior pediatric cataract surgery in 4(15.3%). No improvement in BCVA in 21/26 (80.7%) children led to suspicion of co-existing etiology. Other clues were optic disc pallor (11), subnormal color vision (7), history of parental consanguinity in 7, and preceding febrile illness/rhinitis in 1 child. The DEER taxonomy tool suggested that the most common reasons for diagnostic errors were over-emphasis on amblyopia. Conclusion: Our study suggests that 5% of children diagnosed with amblyopia might have co-existing/alternate etiology. Most common co-existing etiologies were subclinical optic neuropathy, and OMD. No improvement in BCVA, subtle history and examination findings prompted further workup. Not considering co-existing etiologies was the most common reason for an initial overdiagnosis of amblyopia.

Frequency of NMOSD misdiagnosis in a cohort from Latin America: Impact and evaluation of different contributors

Background: Neuromyelitis optica spectrum disorder (NMOSD) misdiagnosis (i.e. the incorrect diagnosis of patients who truly have NMOSD) remains an issue in clinical practice. We determined the frequency and factors associated with NMOSD misdiagnosis in patients evaluated in a cohort from Latin America. Methods: We retrospectively reviewed the medical records of patients with NMOSD, according to the 2015 diagnostic criteria, from referral clinics in six Latin American countries (Argentina, Chile, Paraguay, Colombia, Ecuador, and Venezuela). Diagnoses prior to NMOSD and ultimate diagnoses, demographic, clinical and paraclinical data, and treatment schemes were evaluated. Results: A total of 469 patients presented with an established diagnosis of NMOSD (73.2% seropositive) and after evaluation, we determined that 56 (12%) patients had been initially misdiagnosed with a disease other than NMOSD. The most frequent alternative diagnoses were multiple sclerosis (MS; 66.1%), clinically isolated syndrome (17.9%), and cerebrovascular disease (3.6%). NMOSD misdiagnosis was determined by MS/NMOSD specialists in 33.9% of cases. An atypical MS syndrome was found in 86% of misdiagnosed patients, 50% had NMOSD red flags in brain and/or spinal magnetic resonance imaging (MRI), and 71.5% were prescribed disease-modifying drugs. Conclusions: NMOSD misdiagnosis is relatively frequent in Latin America (12%). Misapplication and misinterpretation of clinical and neuroradiological findings are relevant factors associated with misdiagnosis.

The frequency and characteristics of multiple sclerosis misdiagnosis in Latin America: A referral center study in Buenos Aires, Argentina

Objective: Most contemporary data concerning the frequency and causes of multiple sclerosis (MS) misdiagnosis are from North America and Europe with different healthcare system structure and resources than countries in Latin America. We sought to determine the frequency, and potential contributors to MS misdiagnosis in patients evaluated at an MS referral center in Argentina. Methods: The study was a retrospective medical record review. We included patients evaluated at the MS Clinic at Fleni between April 2013 and March 2021. Diagnoses prior to consultation, final diagnoses after consultation, demographic, clinical and paraclinical data, and treatment were extracted and classified. Results: Seven hundred thirty-six patients were identified. Five hundred seventy-two presented with an established diagnosis of MS and after evaluation, misdiagnosis was identified in 89 (16%). Women were at 83% greater risk of misdiagnosis (p = 0.034). The most frequent alternative diagnoses were cerebrovascular disease, radiological isolated syndrome (RIS), and headache. Seventy-four (83%) of misdiagnosed patients presented with a syndrome atypical for demyelination, 62 (70%) had an atypical brain magnetic resonance imaging (MRI), and 54 (61%) were prescribed disease-modifying therapy. Conclusion: Sixteen percent of patients with established MS were subsequently found to have been misdiagnosed. Women were at higher risk for misdiagnosis. Expert application of the McDonald criteria may prevent misdiagnosis and its associated morbidity and healthcare system cost.

Prevalence and predictors of alternative diagnoses on whole-leg ultrasound negative for acute deep venous thrombosis

BackgroundTo investigate the prevalence, spectrum, and predictors of alternative diagnoses explaining leg symptoms in patients negative for suspected acute deep venous thrombosis (DVT), which can be detected with whole-leg ultrasound.MethodsWe retrospectively analyzed a cohort of 789 patients (median age 70 years, 50.6% women) evaluated with a whole-leg ultrasound examination for suspected acute DVT within one year. All findings in the radiology report were analyzed and electronic chart review was performed to collect clinical information.ResultsUltrasound was negative for acute DVT in 531 patients (67.3%). Among these, alternative diagnoses explaining leg symptoms were seen in 349 patients (65.7%). The most frequent alternative diagnoses were chronic venous insufficiency (147 patients, 27.7%), followed by lymphedema (48 patients, 9.0%) and chronic post-thrombotic changes (41 patients, 7.7%). Patients with alternative diagnoses were older (median 71 vs. 66 years, p = 0.0226), as well as more likely to present with leg swelling (39.5% vs. 23.1%, p = 0.0002), difference in leg circumference (25.5% vs. 14.8%, p = 0.0055) and redness (7.7% vs. 2.7%, p = 0.0213) than patients without alternative diagnosis. Independent predictors of finding alternative diagnoses on whole-leg ultrasound were older age (odds ratio 1.014 per year, p = 0.0119), leg swelling (OR 1.949, p = 0.0020) and history of previous DVT (OR 2.235, p = 0.0154).ConclusionsAlternative diagnoses explaining leg symptoms can be detected on whole-leg ultrasound in two thirds of patients with no evidence of acute DVT. Our data supports performing a comprehensive ultrasound evaluation beyond the venous system, particularly, in older patients, who present with leg swelling and a past history of DVT.

Onset of schizophrenia diagnoses in a large clinical cohort

We aimed to describe the diagnostic patterns preceding and following the onset of schizophrenia diagnoses in outpatient clinics. A large clinical sample of 26,163 patients with a diagnosis of schizophrenia in at least one outpatient visit was investigated. We applied a Continuous Time Hidden Markov Model to describe the probability of transition from other diagnoses to schizophrenia considering time proximity. Although the most frequent diagnoses before schizophrenia were anxiety and mood disorders, direct transitions to schizophrenia usually came from psychotic-spectrum disorders. The initial diagnosis of schizophrenia was not likely to change for two of every three patients if it was confirmed some months after its onset. When not confirmed, the most frequent alternative diagnoses were personality, affective or non-schizophrenia psychotic disorders. Misdiagnosis or comorbidity with affective, anxiety and personality disorders are frequent before and after the diagnosis of schizophrenia. Our findings give partial support to a dimensional view of schizophrenia and emphasize the need for longitudinal assessment.

Rapidly Progressive Alzheimer's Disease: Contributions to Clinical-Pathological Definition and Diagnosis.

Rapidly progressive Alzheimer's disease (rpAD) has recently been recognized as a clinical disease subtype characterized by rapidly progressive cognitive decline and/or short disease duration, and the possible occurrence of early focal neurological signs. Consistently, rpAD represents a relatively frequent alternative diagnosis among cases referred as possible or probable Creutzfeldt-Jakob disease (CJD) to surveillance centers for prion disease worldwide. Indeed, the early clinical differential diagnosis between the two disorders can be challenging given the partial overlap in clinical features and cerebrospinal fluid (CSF) levels of the protein surrogate markers 14-3-3 and total-tau. Although typical AD and rpAD seem to share the neuropathological core features, recent evidence suggests that a distinctive molecular signature involving the structure of amyloid-β aggregates and the proteomic landscape of amyloid plaques may distinguish rpAD from typical AD. Here we review clinical, neuropathological, and molecular features and diagnostic findings, including CSF biomarker data, reported to date in rpAD. Furthermore, we summarize the main clinical, pathological and laboratory features of 27 autopsy confirmed cases of rpAD referred to our center. The results of this retrospective analysis, while largely confirming previously published genetic, clinical, and neuropathological data, suggest a higher prevalence of moderate to severe cerebral amyloid angiopathy in rpAD compared to typical AD, a finding to explore further and validate in a larger patient group.

Low-Dose CT for Evaluation of Suspected Urolithiasis: Diagnostic Yield for Assessment of Alternative Diagnoses.

The purpose of this study is to assess the diagnostic yield of low-dose (LD) CT for alternative diagnoses in patients with suspected urolithiasis. In this retrospective study, we included 776 consecutive patients who underwent unenhanced abdominal CT for evaluation of suspected urolithiasis. All examinations were performed with an LD CT protocol; images were reconstructed using iterative reconstruction. The leading LD CT diagnosis was recorded for each patient and compared with the final clinical diagnosis, which served as the reference standard. The mean (± SD) effective dose of CT was 1.9 ± 0.6 mSv. The frequency of urolithiasis was 82.5% (640/776). LD CT reached a sensitivity of 94.1% (602/640), a specificity of 100.0% (136/136), and an accuracy of 95.1% (738/776) for the detection of urolithiasis. In 93 of 136 patients (68.4%) without urolithiasis, alternative diagnoses were established as the final clinical diagnoses. Alternative diagnoses were most commonly located in the genitourinary (n = 53) and gastrointestinal (n = 18) tracts. LD CT correctly provided alternative diagnoses for 57 patients (61.3%) and was false-negative for five patients (5.4%). The most common clinical alternative diagnoses were urinary tract infections (n = 22). Seven diagnoses missed at LD CT were located outside the FOV. For 43 of all 776 patients (5.5%), neither LD CT nor clinical workup could establish a final diagnosis. The sensitivity, specificity, and accuracy of LD CT for the detection of alternative diagnoses were 91.9% (57/62), 95.6% (43/45), and 93.5% (100/107), respectively. LD CT enables the diagnosis of most alternative diagnoses in the setting of suspected urolithiasis. The most frequent alternative diagnoses missed by LD CT are urinary tract infections or diagnoses located outside the FOV of the abdominopelvic CT scan.

CT angiography in the setting of suspected acute mesenteric ischemia: prevalence of ischemic and alternative diagnoses.

The purpose of the study was to determine the prevalence of ischemic and alternative diagnoses and the diagnostic accuracy of CT angiography (CTA) in the setting of suspected acute mesenteric ischemia (AMI). We included 959 patients undergoing CTA for the evaluation of suspected AMI. The final clinical diagnosis was used to determine the prevalence of ischemic and alternative diagnoses and to calculate the diagnostic accuracy of CTA. Prevalence of diagnoses by age, sex, and admission status was compared using Cochran-Armitage and χ 2 tests. Prevalence was 18.8% (180/959) for AMI and 61.2% (587/959) for specific alternative diagnoses. In the remaining 20.0% (192/959), no clear clinical diagnosis was established. The most frequent alternative diagnoses were small-bowel obstruction (10.4%; 61/587), infectious colitis (8.7%; 51/587), pneumonia (6.5%; 38/587), cholecystitis (6.1%; 36/587), and diverticulitis (5.6%; 33/587). Prevalence of specific alternative diagnoses varied significantly according to both age (p<.013) and admissions status (p<0.001). CTA had a sensitivity and specificity for diagnosing AMI of 89.4%/99.5% and for alternative diagnoses of 86.7%/96.9%, respectively. In the setting of suspected AMI, the prevalence of ischemic and alternative diagnoses varies significantly by age, sex, and admission status. CTA provides for rapid and non-invasive assessment of ischemic and alternative diagnoses with high diagnostic accuracy.

Alternative diagnoses in patients in whom the GP considered the diagnosis of pulmonary embolism.

Pulmonary embolism (PE) often presents with nonspecific symptoms and may be an easily missed diagnosis. When the differential diagnosis includes PE, an empirical list of frequently occurring alternative diagnoses could support the GP in diagnostic decision making. To identify common alternative diagnoses in patients in whom the GP suspected PE but in whom PE could be ruled out. To investigate how the Wells clinical decision rule for PE combined with a point-of-care d-dimer test is associated with these alternative diagnoses. Secondary analysis of the Amsterdam Maastricht Utrecht Study on thrombo-Embolism (Amuse-2) study, which validated the Wells PE rule combined with point-of-care d-dimer testing in primary care. All 598 patients had been referred to and diagnosed in secondary care. All diagnostic information was retrieved from the GPs' medical records. In 516 patients without PE, the most frequent alternative diagnoses were nonspecific thoracic pain/dyspnoea (42.6%), pneumonia (13.0%), myalgia (11.8%), asthma/chronic obstructive pulmonary disease (4.8%), panic disorder/hyperventilation (4.1%) and respiratory tract infection (2.3%). Pneumonia occurred almost as frequent as PE. Patients without PE with either a positive Wells rule (>4) or a positive d-dimer test, were more often (odds ratio = 2.1) diagnosed with a clinically relevant disease than patients with a negative Wells rule and negative d-dimer test. In primary care patients suspected of PE, the most common clinically relevant diagnosis other than PE was pneumonia. A positive Wells rule or a positive d-dimer test are not only positively associated with PE, but also with a high probability of other clinically relevant disease.

The metabolic brain network in patients with Parkinson's disease based on (18)F-FDG PET imaging: evaluation of neuronal injury and regeneration.

Over the past two decades, the development of functional imaging methods has greatly promoted our understanding on the changes of neurons following neurodegenerative disorders, such as Parkinson's disease (PD). The application of a spatial covariance analysis on 18F-FDG PET imaging has led to the identification of a distinctive disease-related metabolic pattern. This pattern has proven to be useful in clinical diagnosis, disease progression monitoring as well as assessment of the neuronal changes before and after clinical treatment. It may potentially serve as an objective biomarker on disease progression monitoring, assessment, histological and functional evaluation of related diseases. PD is one of the most common neurodegenerative disorders in the elderly. It is characterized by progressive loss of dopamine neurons in the substantia nigra pars compacta. Throughout the course of disease, the most obvious symptoms are movement-related, such as resting tremor, muscle rigidity, hypokinesia and postural instability (Worth, 2013). Currently, a definite diagnosis of PD is made by clinical evaluation with at least 2 years of follow-up (Hughes et al., 2002; Bhidayasiri and Reichmann, 2013), due to the overlap of motor symptoms between early PD and atypical parkinsonism including multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). However, this classic diagnostic criterion does not benefit the early diagnosis of disease. The prognostic outcome and treatment option are substantially different between PD and atypical parkinsonism. Thus it is critical to develop biomarkers for earlier and more accurate diagnosis of PD. Generally, appropriate diagnostic biomarker for PD ought to cover several key characteristics: (i) minimal invasiveness to detect the biomarker in easily accessible body tissue or fluids, (ii) excellent sensitivity to explore the patients with PD, (iii) high specificity to prevent false-positive results in PD-free individuals, and (iv) robustness against potential affecting factors. A PD-related spatial covariance pattern (PDRP) with quantifiable expression on 18F-FDG PET imaging has been gradually detected using a spatial covariance method during the last two decades and it has been demonstrated to be the right diagnostic biomarker for PD (Eidelberg et al., 1994). PDRP has proven not only to be effective in early discrimination of PD from atypical parkinsonian disorders, but also to be able to assess the disease progression and treatment response. Thus it is considered as a multifunctional biomarker. In this review, we aim to provide an overview of the development in pattern-based biomarker for PD.

Herbal hepatotoxicity

Alternative explanations are common in suspected drug-induced liver injury (DILI) and account for up to 47.1% of analyzed cases. This raised the question of whether a similar frequency may prevail in cases of assumed herb-induced liver injury (HILI). We searched the Medline database for the following terms: herbs, herbal drugs, herbal dietary supplements, hepatotoxic herbs, herbal hepatotoxicity, and herb-induced liver injury. Additional terms specifically addressed single herbs and herbal products: black cohosh, Greater Celandine, green tea, Herbalife products, Hydroxycut, kava, and Pelargonium sidoides. We retrieved 23 published case series and regulatory assessments related to hepatotoxicity by herbs and herbal dietary supplements with alternative causes. The 23 publications comprised 573 cases of initially suspected HILI; alternative causes were evident in 278/573 cases (48.5%). Among them were hepatitis by various viruses (9.7%), autoimmune diseases (10.4%), nonalcoholic and alcoholic liver diseases (5.4%), liver injury by comedication (DILI and other HILI) (43.9%), and liver involvement in infectious diseases (4.7%). Biliary and pancreatic diseases were frequent alternative diagnoses (11.5%), raising therapeutic problems if specific treatment is withheld; pre-existing liver diseases including cirrhosis (9.7%) were additional confounding variables. Other diagnoses were rare, but possibly relevant for the individual patient. In 573 cases of initially assumed HILI, 48.5% showed alternative causes unrelated to the initially incriminated herb, herbal drug, or herbal dietary supplement, calling for thorough clinical evaluations and appropriate causality assessments in future cases of suspected HILI.

Prevalence, Etiology, and Outcome of Catheterization Laboratory False Alarms in Patients With Suspected ST-Elevation Myocardial Infarction

To investigate the prevalence, causes and outcome of catheterization laboratory false alarms (CLFAs) in a regional primary angioplasty network. A prospective registry of 1,662 patients referred for primary angioplasty between January 2003 and August 2008 was reviewed to identify CLFAs (i.e. when no culprit coronary lesion could be found). No culprit coronary lesion could be identified in 120 patients (7.2%; 95% confidence interval [CI], 5.9-8.5%). Of these, 104 (6.3%, 95% CI, 5.1-7.4%) had a discharge diagnosis other than ST-elevation myocardial infarction, 91 (5.5%; 95% CI, 4.3-6.6%) had no significant coronary disease, and 64 (3.8%; 95% CI, 2.9-4.8%) tested negative for cardiac biomarkers. The most frequent alternative diagnoses were: previous Q-wave myocardial infarction (18 cases), nonspecific ST-segment abnormalities (11), pericarditis (10) and transient apical dyskinesia (10). The 30-day mortality rate was similar in patients with and without culprit lesions (5.8% vs. 5.8%; P=.99). The prevalence of CLFAs was slightly higher in patients not previously evaluated by a cardiologist and referred from emergency departments in hospitals without catheterization laboratories than in those referred by cardiologists from emergency departments at hospitals with such facilities (9.5% vs. 6.1%; P=.02; odds ratio=1.64; 95% CI, 1.08-2.5). The prevalence of CLFAs was not significantly higher in patients referred by physicians with out-of-hospital emergency medical services (7.2%; P=.51; odds ratio=1.37; 95% CI, 0.79-2.37). The prevalence of CLFAs was 7.2%, with the criterion of no culprit coronary lesion. Our findings suggest that different patterns of referral to catheterization laboratories could account for small variations in the prevalence of CLFAs.

Suspicion of pulmonary embolism in outpatients: nonspecific chest pain is the most frequent alternative diagnosis.

Several recent studies have focused on identifying clinical predictors of embolism. However, although pulmonary embolism is ruled out in 70-85% of the patients in whom it is suspected, data on the clinical characteristics and discharge diagnosis of such patients are scarce. Our aim was to evaluate whether clinical characteristics would allow predicting alternative diagnoses other than pulmonary embolism thereby ruling out venous thromboembolism. Retrospective analysis. Emergency centres of two teaching and general hospitals. A total of 1090 consecutive outpatients admitted for clinically suspected pulmonary embolism and a diagnosis established by a validated algorithm and a 3-month follow-up. Discharge diagnoses of patients in whom pulmonary embolism was ruled out were identified and regrouped into two categories: (i) nonspecific chest pain and (ii) diagnosis other than pulmonary embolism. Predictive accuracy of clinical and laboratory variables for diagnosing nonspecific chest pain was assessed by univariate and multivariate analysis. In patients without pulmonary embolism, nonspecific chest pain (parietal chest pain, chest pain of unknown origin and pleuritis) was the most frequent discharge diagnosis (n = 334, 31% of the entire cohort, 43% of the patients without pulmonary embolism). Other patients without pulmonary embolism had a wide variety of diagnoses, of which the most frequent were bronchopneumonia (6.0% of the entire cohort) and heart failure (5.2%). In the multivariate analysis, seven variables were strongly associated with nonspecific chest pain: younger age (below 40 years), female gender, respiratory rate below 20 min(-1), heart rate below 100 min(-1), and absence of recent immobilization, dyspnoea and haemoptysis. Two of the 24 patients in whom all those characteristics were present had pulmonary embolism (8%, 95% CI 3-22%). The most frequent discharge diagnosis in emergency ward patients in whom pulmonary embolism is ruled out is nonspecific chest pain. A clinical model did not allow to predict nonspecific chest pain with enough accuracy to rule out pulmonary embolism without further testing. Whether a more precise characterization of chest pain might allow an accurate identification of such patients deserves further study.

Pulmonary atelectasis: a frequent alternative diagnosis in patients undergoing CT-PA for suspected pulmonary embolism.

The purpose of the study was to evaluate the prevalence of atelectasis as an alternative diagnosis in patients who underwent computed tomographic pulmonary angiography (CT-PA) for suspected pulmonary embolism (PE), and to contrast the pathophysiology of pulmonary atelectasis and PE, both of which are associated with dyspnea and hypoxemia. We retrospectively identified 144 consecutive emergency department patients (n=49) and inpatients (n=95) admitted between July 2001 and June 2002 who were evaluated with CT-PA for suspected PE. There were 98 women and 46 men with a mean age of 58 years (range 27-95 years). Each CT report was reviewed for PE, the words "atelectasis," "collapse," and/or "volume loss," findings known to predispose to atelectasis, and alternative diagnoses. CT scans of those with PE and those with atelectasis were reviewed. Each case was categorized into one of three groups, as follows: group 1, PE; group 2, atelectasis of three or more segments and no PE; group 3, neither PE nor atelectasis. PaO2 was documented, when available (n=115), with PaO2 >100 mmHg recorded as 100 mmHg. Reports for group 3 were reviewed for alternative diagnoses. Thirteen percent of the study population (19/144, group 1) had PE, and two of them had concomitant atelectasis; mean PaO2 was 69 mmHg (range 38-100 mmHg). Nineteen percent of the study population (27/144, group 2) had atelectasis of three or more segments without PE; mean PaO2 was 73 mmHg (range 45-100 mmHg). Sixty-eight percent of the study population (98/144, group 3) had neither PE nor atelectasis; mean PaO2 was 79 mmHg (range 36-100 mmHg). There was a significant difference in the PaO2 between groups 1 and 3 (Student's t-test), with group 2 intermediate. Seventy percent of group 2 (19/27) had at least one finding predisposing to atelectasis: central bronchial abnormality (n=6), moderate or larger pleural effusion (n=11), pleural mass, pneumothorax, elevated hemidiaphragm, and severe kyphosis (the last four all n=1 each), versus 16% (3/19) of group 1 ( P<0.05). Sixty-three percent of group 3 (62/98) had one or more alternative diagnoses on CT that explained the patient's symptoms as follows: pneumonia (28%, 27/98), other lung disease (18%, 18/98), congestive heart failure (13%, 13/98), and malignancy (13%, 13/98). Pulmonary atelectasis was common in patients undergoing CT-PA for suspected PE, equaling pneumonia as the most common alternative diagnosis. Most patients with atelectasis had predisposing findings on CT. Pulmonary atelectasis and PE cause similar symptoms by different mechanisms of ventilation-perfusion mismatch.

CT evaluation of appendicitis and diverticulitis. Part II: Diverticulitis

CT has become the primary imaging modality for evaluation of possible diverticulitis. In studies of patients taken to surgery for suspected diverticulitis without first undergoing CT, 25–33 % of resected specimens show no inflammation. The overall accuracy of CT in establishing or excluding the diagnosis is between 84 and 99 %. In patients without diverticulitis, an alternative diagnosis is seen in 50–58 % of cases. The appearance of carcinoma with perforation and diverticulitis may be the same, and, as a result, the degree of certainty in the diagnosis should be stated. Techniques include use of either oral and intravenous contrast or rectally administered contrast. No case of colonic perforation due to rectally administered water-soluble contrast for CT has been reported, although there have been cases of perforation using barium and fluoroscopy. All techniques scan the entire abdomen and pelvis since there are frequent alternative diagnoses seen beyond the area of initial pain.

Salmonella Lung Involvement in Patients With HIV Infection

To determine the frequency, clinical features, and outcome of lung involvement in HIV-infected patients having nontyphoid strains of Salmonella bacteremia. A retrospective clinical study. We studied the records of all HIV-infected patients with Salmonella bacteremia diagnosed at a university tertiary hospital from January 1987 to December 1995. Lung involvement was found in 18 (35.3%) of 51 HIV-infected individuals with Salmonella bacteremia. Six of 18 (33.3%) were diagnosed as having definite Salmonella pulmonary infection by isolation of Salmonella from respiratory specimens, while probable Salmonella lung disease was considered in two patients who developed lung abscesses without the identification of any pathogen. Predisposing factors for focal disease, such as prior lung disease or Salmonella serotype, were equally prevalent regardless of the presence of Salmonella pulmonary involvement. Cavitary infiltrates or abscess formation were seen in five of the eight patients. With the exception of one patient coinfected with Nocardia asteroides who died 1 month later, all patients were cured with antibiotic treatment. Superinfection with other pulmonary pathogens (10 cases, 56%) was more frequent than Salmonella pneumonia; the most frequent alternative diagnosis was Pneumocystis carinii pneumonia (5 cases, 28%), pyogenic bacterial infection (17%), and tuberculosis (11%). In HIV-infected patients with Salmonella bacteremia, lung involvement is frequent, although there were no significant factors to explain this association. Cavitary disease was the most common radiologic pattern, and focal lung disease due to Salmonella does not seem to be associated with a worse prognosis. Coinfection and superinfection with other respiratory pathogens are more common than isolated Salmonella lung disease, and therefore, additional diagnostic procedures must be considered in the evaluation of these patients.

Influence of negative ultrasound findings on the management of in- and outpatients with suspected deep-vein thrombosis

Real-time ultrasonography (US) was used as a single non-invasive method in the management of 174 patients (56 inpatients and 118 outpatients) with suspected deep-vein thrombosis (DVT). Therapeutic decisions were based on the results of ultrasonography alone. If the US examination was abnormal anticoagulant treatment was started. If the initial US examination was normal, no treatment was given and the patient underwent repeated testing and physical examination after 1 day, 7 days and 3 months. In the outpatient group, 1.3% of the ultrasonographic negative patients developed thromboembolic complications (95% confidence limits, 0.03–7.21%). None of the initial ultrasonographic negative patients developed proximal DVT after 1 day and 7 days. In the inpatient group, 10% of the ultrasonographic negative patients developed thromboembolic complications (95% confidence limits, 1.2–31.7%). In 18% of the ultrasonographic negative patients an alternative, unexpected diagnosis was obtained by ultrasound. The most frequent alternative diagnosis was a popliteal cyst. The results indicate that US alone appears to be a safe diagnostic method in the management of outpatients with suspected DVT. In the inpatient group further research is required for definite recommendations regarding a safe ultrasound follow-up schedule.

The nature of unexplained chronic aminotransferase elevations of a mild to moderate degree in asymptomatic patients.

To determine the nature of unexplained chronic serum aspartate aminotransferase elevations of a mild to moderate degree in asymptomatic patients, we performed systematic clinical, biochemical and histologic examinations in 47 individuals who had been screened for virus-, alcohol- or drug-related disease. Serum aspartate aminotransferase levels ranged from 3- to 8-fold normal (mean: 156 +/- 7 units per liter) for at least 6 months (mean: 30 +/- 6 months). Serum alanine aminotransferase levels were also increased but to a lesser degree in most patients. Thirty-four patients (72%) had histologic features of chronic active hepatitis, including 16 with cirrhosis. Ten patients (21%) had steatohepatitis and three (6%) had miscellaneous disorders. Patients with chronic active hepatitis and cirrhosis could not be distinguished from counterparts without cirrhosis by individual clinical or laboratory findings. Antinuclear or smooth muscle antibodies were detected in 18 of the patients with chronic active hepatitis (53%). All patients with steatohepatitis were women, and they had laboratory changes at presentation, including seropositivity for antinuclear antibodies, that overlapped with those of patients with chronic active hepatitis. We conclude that asymptomatic patients with unexplained chronic aspartate aminotransferase elevations of a mild to moderate degree frequently have chronic active hepatitis and that many have cirrhosis. Immunoserologic findings compatible with autoimmune hepatitis are commonly present. Steatohepatitis is the most frequent alternative diagnosis, especially in women, and it is not excluded by the presence of antinuclear antibodies. Differentiation of the disorders is possible only by histologic examination.

Admission pattern and diagnostic stability among unipolar and bipolar manic-depressive patients.

The instability of the diagnoses in a psychiatric register causes practical problems when groups of probands with specific diagnoses are selected for further studies. A cohort of 3,062 first admissions with at least one manic-depressive admission was followed for 5-7 years. 623 had at least one admission for mania and were considered bipolar. The percentage of patients who changed their diagnoses was highest at first readmission; at each later readmission about 10% of the bipolars and 25% of the unipolars changed from manic-depressive psychosis and a similar number changed from other diagnoses to manic-depressive psychosis. Compared with the diagnostic distribution of all register cases, reactive psychoses were more frequent than expected as former diagnoses and schizophrenia as later diagnosis. Neuroses and character deviations were frequent alternative diagnoses among unipolars, not among bipolars. The consequences of different selection criteria for the composition of proband groups are discussed.