Combining neural network predictions for medical diagnosis

We present our results from combining the predictions of an ensemble of neural networks for the diagnosis of hepatobiliary disorders. To improve the accuracy of the diagnosis, we train the second level networks using the outputs of the first level networks as input data. The second level networks achieve an accuracy that is higher than that of the individual networks in the first level. Compared to the simple method which averages the outputs of the first level networks, the second level networks are also more accurate. We discuss how the overall predictive accuracy can be improved by introducing bias during the training of the level one networks.     

Combining cytomorphology and serology for the diagnosis of cat scratch disease

Cat scratch disease (CSD) is a self limited zoonotic disease that presents most commonly as a regional lymphadenopathy. We are reporting a case of a 25-year-old male patient who presented with fever and large right inguinal lymphadenopathy. The diagnosis of cat scratch disease was confirmed based on the characteristic cytopathological features on aspirate smears from the lymph node and the serological titers for Bartonella henselae. This case report emphasizes the importance of combining Bartonella serology, and cytopathology in the diagnostic work-up of febrile lymphadenopathy and suspected CSD since the culture of this organism is arduous.     

Combining psychotherapy and antidepressants in the treatment of depression

OBJECTIVE: To compare the efficacy of antidepressants with that of antidepressants plus psychotherapy ("combined therapy") in the treatment of depression. METHODS: 6 month randomised clinical trial of antidepressants (N=84) and combined therapy (N=83) in ambulatory patients with Major Depression and a 17-item HDRS baseline score of at least 14 points. The antidepressant protocol provides for three successive steps in case of intolerance or inefficacy: fluoxetine, amitriptyline and moclobemide. The combined therapy condition consists, in addition to pharmacotherapy, of 16 sessions of Short Psychodynamic Supportive Psychotherapy. Efficacy is assessed using the 17-item HDRS, the CGI of Severity and of Improvement, the depression subscale of the SCL-90, and the Quality of Life Depression Scale. The data analysis is conducted on three samples: the intention-to-treat sample, the per protocol sample and the observed cases sample. RESULTS: After randomisation, 32% of the patients refused the proposed pharmacotherapy while 13% refused the proposed combined therapy. In 24 weeks, 40% of the patients who started with the pharmacotherapy stopped medication; 22% of those receiving the combined therapy did so. The difference in success rates is statistically significant, favouring combined therapy, in 23%, 31% and 62% of the patients after 8, 16 and 24 weeks of treatment, respectively. At week 24, the mean success rate is 40.7% in the pharmacotherapy group and 59.2% in the combined therapy group. CONCLUSION: Patients found combined treatment significantly more acceptable, they were significantly less likely to drop out of combined therapy and, ultimately, significantly more likely to recover. Combined therapy is preferable to pharmacotherapy in the treatment of ambulatory patients with major depression.     

Combining desloratadine and pseudoephedrine in the treatment of seasonal allergic rhinitis

Nonsedating antihistamines are a first-line therapy in the management of allergic rhinitis. They relieve the majority of the histamine-mediated symptoms of the condition, including rhinorrhea, sneezing, and pruritus. The nonsedating antihistamine desloratadine is effective in alleviating the symptoms of both seasonal and perennial allergic rhinitis. It may also have some decongestant properties, and thus help to alleviate nasal congestion. Administering desloratadine in combination with the decongestant pseudoephedrine may offer allergic rhinitis patients with moderate-to-severe nasal congestion the benefits of desloratadine’s effectiveness for alleviating histamine-mediated symptoms plus pseudoephedrine’s relief from nasal congestion. This drug profile reviews a combination therapy containing desloratadine and pseudoephedrine, approved in the USA for the relief of the symptoms of seasonal allergic rhinitis, including nasal congestion.     

紧张性头痛的心理与药物综合治疗临床观察

目的 :通过随机分组、临床对照研究 ,对紧张性头痛的心理与药物的综合治疗模式进行客观评价。方法 :将 84例紧张性头痛患者 ,随机分为实验组和对照组。对照组给予常规药物治疗 ,实验组则在常规药物治疗的同时 ,由具备心理治疗技巧的医生给予心理治疗 ,每周 2至 3次 ,每疗程 6次。待一疗程结束后评定疗效 ,且随访至少一年。结果 :实验组总有效率为 95 2 4% ,显效率为 66 67% ,与对照组总有效率、显效率分别为 69 0 5 %和 3 8 10 %相比较 ,差别具有统计学意义 (P <0 0 1)。结论 :心理与药物的综合治疗模式对紧张性头痛是一种非常有效的治疗方式 ;心理治疗技巧影响治疗效果     

石杉碱及氯硝西泮治疗慢性失眠症的临床观察

目的 :评价石杉碱、氯硝西泮治疗慢性失眠症的临床疗效。方法 :5 3例长期服用各类催眠药物无效的慢性失眠症患者在停用原药物三天后 ,进入连续二周的夜间睡前 30分钟服用氯硝西泮 2mg (A阶段 ) ;然后连续四周的石杉碱 ,上午、中午各服用 10 0ug ;氯硝西泮夜间睡前 30分钟服用 2mg (B阶段 ) ;最后连续四周 ,自选氯硝西泮夜间用量 (C阶段 )。A、B、C三阶段分别登记日间觉醒及夜间睡眠时间及其每日二者的平均比值 ,每日氯硝西泮用量及每阶段前后匹兹堡睡眠质量指数。结果 :昼夜交替服用石杉碱、氯硝西泮B、C阶段治疗与单一夜间口服氯硝西泮的A阶段比较显示 ,通过延长夜间睡眠时间 ,使睡眠一觉醒时间比值降至 1:4 7± 2 1,较A阶段的 1:6 3± 3 5有明显下降 (P <0 0 2 ) ,同时提高了睡眠质量 ,匹兹堡睡眠质量指数评分值由A阶段的 14 2± 4 5降至C阶段的 8 3± 3 7(P <0 0 1)。并且在C阶段中 ,平均每例患者的用量为 0 8mg± 0 2 2mg ,与A、B阶段的 2mg降低约 6 0 % ,其中有 16例患者在C阶段末期停用氯硝西泮。结论 :石杉碱、氯硝西泮昼夜服用治疗慢性失眠症通过延长睡眠时间而改善睡眠觉醒周期节律的同时亦提高睡眠质量。并逐步减少了氯硝西泮用量 ,其疗效较原夜间服用氯硝西泮方案更有效     

Combining the transmission disequilibrium test and case-control methodology using generalized logistic regression

To study the role of genetic factors in the etiology, susceptibility, or severity of disease, several methods are available. In a transmission disequilibrium test, genotypes of cases are compared to those of their parents to explore whether a specific allele, or marker, at a locus of interest appears to be transmitted in excess of what is expected on the basis of Mendelian inheritance. Such apparent excess transmission indicates that cases are being selected for that allele, thereby providing evidence that this allele is a risk factor for disease. In case-control studies, genotypes of cases are compared to those of controls from the same population to identify whether a specific allele is associated with disease. If so, either the allele at this locus or one in linkage disequilibrium with it may be causally related to the etiology of the disease. Here, we discuss the problem of combining a transmission disequilibrium test and a case-control comparison, in order to integrate all available information, and thereby increase statistical power. As the same cases are used in both approaches, the two results are not independent. However, parents of cases can be independently compared to controls. Both the issue of testing for a genetic effect and the estimation of relative risks under the multiplicative model using generalized logistic regression are discussed.     

Food allergy: diagnosis and treatment

The increasing awareness by the medical profession, as well as the public, of food allergy imposes the parallel task of accurate diagnosis and proper treatment. A carefully obtained medical history and a properly conducted elimination-challenge test are the most valuable as well as the least expensive procedures for diagnosis. Other selected in vivo and in vitro tests may enhance the diagnostic ability and may verify the immunologic basis of the food-induced reaction. Treatment is basically dietary avoidance, and its success depends on several factors. Pharmacologic agents may be needed for symptomatic treatment, and in certain instances for prophylaxis. The need still exists for developing an effective procedure of hyposensitization.     

Gaucher disease: diagnosis and treatment

Gaucher's disease is the most common lysosomal storage disorder. It was identified in 1882 by Phillipe Gaucher, a French dermatologist. However, it was not until 1965 that Gaucher disease was found to be due to a deficiency in the enzyme glucocerebrosidase (EC 3.2.1.45) which breaks down glucocerebroside, a cell membrane component. The deficiency in this enzyme leads to an accumulation of glucocerebroside within the lysosomes of macrophages throughout the body. Gaucher's disease is classified into three types: type 1 (non-neuronopathic), type 2 (acute neuronopathic), and type 3 (subacute neuronopathic). Of the three, type 1 is the most common, affecting one in 40,000-200,000 people and having a high prevalence among Ashkenazi Jews, affecting one in 450-1500. The signs and symptoms of type 1 disease demonstrate marked heterogeneity, from asymptomatic or mildly symptomatic, to severe disability with disfigurement and even death. Hepatosplenomegaly and thrombocytopenia are well documented. Less well-recognized are often insidious skeletal complications which affect the majority of type 1 patients and which are its most debilitating feature. In addition to clinical suspicion, some morphologic, hematologic and biochemical indicators can help establish the diagnosis. However, definitive diagnosis is only made by determining the catalytic activity of the lysosomal enzyme glucocerebrosidase. Confirmation of heterozygosity requires the use of molecular biotechnology methods. About 150 mutations of the glucocerebrosidase gene have been identified in patients with Gaucher's disease, some of which are predictive of phenotype. The history of treatment of Gaucher disease started with splenectomy and continued with bone marrow transplantation, before the recent introduction of safe and effective enzyme replacement therapy. In Croatia, nine patients with type 1 Gaucher's disease have been identified so far. Seven patients are on enzyme replacement therapy, and past results demonstrated significant improvement in all clinical symptoms, without development of any side effects. However, new treatments, such as substrate balance therapy and gene therapy, may become available within the next few years. The place, if any, that such therapies will have in the treatment of patients with Gaucher's disease will be dependent on the results of clinical studies currently in progress.     

The diagnosis and treatment of toxoplasmosis

Toxoplasma gondii is a common cause of infection in humans the world over. Toxoplasmosis, the disease caused byToxoplasma gondii, is observed in only a small portion of those infected. The most serious consequences of the infection are seen in the offspring of women who acquire the infection during pregnancy and in immunodeficient patients. Methods of diagnosis, their interpretation, treatment regimens, and preventive measures differ for each category of patients at risk. Each of these points is reviewed with emphasis on applicability to different clinical situations.     

Understanding variation for clinical governance: an illustration using the diagnosis and treatment of sore throat.

BACKGROUND: The aim of clinical governance is to improve clinical care. An understanding of the information contained in variation is central to any improvement effort. We must distinguish between variation intrinsic to a process (common cause variation) and variation caused by extrinsic factors (special cause variation). The control chart is a method of distinguishing between these two kinds of variation: it is used in industry to effect improvement and may be useful in primary care. AIM: To illustrate the use of control charts to distinguish between common cause and special cause variation and to guide appropriate action. DESIGN OF STUDY: Analysis of diagnostic and treatment decisions for sore throat. SETTING: Single practice in the West Midlands. METHODS: We identified each general practitioner's (GP's) consultations for sore throat over a two-year period. We grouped these into two diagnostic categories (tonsillitis and non-tonsillar throat infection) and two treatment categories (antibiotics and no antibiotics). These data were illustrated graphically as XY control charts. RESULTS: In this practice, a special cause affects one GP's diagnosis--he is less likely to use the term 'tonsillitis'. A special cause also affects his treatment decisions--he is more likely to prescribe antibiotics. Diagnostic and treatment differences between the remaining GPs are consistent with common cause variation. CONCLUSION: In this practice, action to improve the quality of diagnosis and treatment of sore throat shouldfocus on investigating why one practitioner's diagnosis and treatment differs from that of his colleagues. Control chart analysis is valuable because it enables users to obtain practical guidance for action.