Items in AFP with MESH term: Algorithms
ABSTRACT: Acute interstitial nephritis is an important cause of acute renal failure resulting from immune-mediated tubulointerstitial injury, initiated by medications, infection, and other causes. Acute interstitial nephritis may be implicated in up to 15 percent of patients hospitalized for acute renal failure. Clinical features are essentially those of acute renal failure from any cause, and apart from a history of new illness or medication exposure, there are no specific history, physical examination, or laboratory findings that distinguish acute interstitial nephritis from other causes of acute renal failure. Classic findings of fever, rash, and arthralgias may be absent in up to two thirds of patients. Diagnostic studies such as urine eosinophils and renal gallium 67 scanning provide suggestive evidence, but they are unable to reliably confirm or exclude the diagnosis of acute interstitial nephritis. Renal biopsy remains the gold standard for diagnosis, but it may not be required in mild cases or when clinical improvement is rapid after removal of an offending agent or medication. The time until removal of such agents, and renal biopsy findings, provide the best prognostic information for return to baseline renal function. Corticosteroids appear to provide some benefit in terms of clinical improvement and return of renal function, but no controlled clinical trials have been conducted to confirm this.
ABSTRACT: Gait disorders in the elderly are common and in most cases cannot be treated medically or surgically. Therefore, treatment often relies on ambulatory devices such as canes, crutches, and walkers. Before selecting a device, the patient should be evaluated to define whether one or both upper extremities are required to achieve balance or bear weight. Patients requiring only one upper extremity can use a cane, while patients requiring both upper extremities are best served by forearm crutches or walkers. The patient's need to bear weight through the device will help the physician choose a specific device. When measuring the device, anatomic landmarks and the angle of the elbow must be taken into consideration. Because time often is limited during a routine office visit, a physical therapist often can provide further training for patients learning to use such a device.
Tremor - Article
ABSTRACT: Tremor, a rhythmic, involuntary, oscillatory movement of body parts, is the most common movement disorder. Tremors are classified as rest or action tremors. Rest tremor occurs when the affected body part is completely supported against gravity. Action tremors are produced by voluntary muscle contraction and are further divided into postural, isometric, or kinetic tremors. This article describes clinical signs and symptoms of six tremor syndromes, including physiologic tremor, essential tremor, Parkinson's disease, toxic and drug-induced tremor, cerebellar tremor, and psychogenic tremor, and presents a detailed diagnostic approach to tremor. Although new technologies such as positron emission tomography and single photon emission computed tomography are under investigation for possible use in diagnosing specific tremor syndromes, they have no widespread applicability or use at this time. The history and physical examination remain the most important diagnostic tools available to clinicians in identifying and classifying tremor syndromes.
Diagnostic Approach to Tinnitus - Article
ABSTRACT: Tinnitus is a common disorder with many possible causes. Most cases of tinnitus are subjective, but occasionally the tinnitus can be heard by an examiner. Otologic problems, especially hearing loss, are the most common causes of subjective tinnitus. Common causes of conductive hearing loss include external ear infection, cerumen impaction, and middle ear effusion. Sensorineural hearing loss may be caused by exposure to excessive loud noise, presbycusis, ototoxic medications, or Meniere's disease. Unilateral hearing loss plus tinnitus should increase suspicion for acoustic neuroma. Subjective tinnitus also may be caused by neurologic, metabolic, or psychogenic disorders. Objective tinnitus usually is caused by vascular abnormalities of the carotid artery or jugular venous systems. Initial evaluation of tinnitus should include a thorough history, head and neck examination, and audiometric testing to identify an underlying etiology. Unilateral or pulsatile tinnitus may be caused by more serious pathology and typically merits specialized audiometric testing and radiologic studies. In patients who are discomforted by tinnitus and have no remediable cause, auditory masking may provide some relief.
Abnormal Uterine Bleeding - Article
ABSTRACT: Abnormal uterine bleeding is a common presenting symptom in the family practice setting. In women of childbearing age, a methodical history, physical examination, and laboratory evaluation may enable the physician to rule out causes such as pregnancy and pregnancy-related disorders, medications, iatrogenic causes, systemic conditions, and obvious genital tract pathology. Dysfunctional uterine bleeding (anovulatory or ovulatory) is diagnosed by exclusion of these causes. In women of childbearing age who are at high risk for endometrial cancer, the initial evaluation includes endometrial biopsy; saline-infusion sonohysterography or diagnostic hysteroscopy is performed if initial studies are inconclusive or the bleeding continues. Women of childbearing age who are at low risk for endometrial cancer may be assessed initially by transvaginal ultrasonography. Postmenopausal women with abnormal uterine bleeding should be offered dilatation and curettage; if they are poor candidates for general anesthesia or decline dilatation and curettage, they may be offered transvaginal ultrasonography or saline-infusion sonohysterography with directed endometrial biopsy. Medical management of anovulatory dysfunctional uterine bleeding may include oral contraceptive pills or cyclic progestins. Menorrhagia is managed most effectively with nonsteroidal anti-inflammatory drugs or the levonorgestrel intrauterine contraceptive device. Surgical management may include hysterectomy or less invasive, uterus-sparing procedures.
ABSTRACT: Systemic lupus erythematosus is a multisystem inflammatory disease that is often difficult to diagnose. Before the diagnosis can be established, four of 11 clinical and laboratory criteria must be met. Antinuclear antibody titer is the primary laboratory test used to diagnose systemic lupus erythematosus. Because of the low prevalence of the disease in primary care populations, the antinuclear antibody titer has a low predictive value in patients without typical clinical symptoms. Therefore, as specified by the American College of Rheumatology, this titer should be obtained only in patients with unexplained involvement of two or more organ systems. Patients with an antinuclear antibody titer of 1:40 and characteristic multiorgan system involvement can be diagnosed with systemic lupus erythematosus without additional testing; however, patients with an antibody titer of 1:40 who fail to meet full clinical criteria should undergo additional testing, including tests for antibody to double-stranded DNA antigen and antibody to Sm nuclear antigen. While an antinuclear antibody titer of less than 1:40 usually rules out systemic lupus erythematosus, patients with persistent, characteristic multisystem involvement may be evaluated for possible antinuclear antibody-negative disease.
ABSTRACT: Fever of unknown origin (FUO) in adults is defined as a temperature higher than 38.3 degrees C (100.9 degrees F) that lasts for more than three weeks with no obvious source despite appropriate investigation. The four categories of potential etiology of FUO are classic, nosocomial, immune deficient, and human immunodeficiency virus-related. The four subgroups of the differential diagnosis of FUO are infections, malignancies, autoimmune conditions, and miscellaneous. A thorough history, physical examination, and standard laboratory testing remain the basis of the initial evaluation of the patient with FUO. Newer diagnostic modalities, including updated serology, viral cultures, computed tomography, and magnetic resonance imaging, have important roles in the assessment of these patients.
Hemolytic Anemia - Article
ABSTRACT: Hemolysis presents as acute or chronic anemia, reticulocytosis, or jaundice. The diagnosis is established by reticulocytosis, increased unconjugated bilirubin and lactate dehydrogenase, decreased haptoglobin, and peripheral blood smear findings. Premature destruction of erythrocytes occurs intravascularly or extravascularly. The etiologies of hemolysis often are categorized as acquired or hereditary. Common acquired causes of hemolytic anemia are autoimmunity, microangiopathy, and infection. Immune-mediated hemolysis, caused by antierythrocyte antibodies, can be secondary to malignancies, autoimmune disorders, drugs, and transfusion reactions. Microangiopathic hemolytic anemia occurs when the red cell membrane is damaged in circulation, leading to intravascular hemolysis and the appearance of schistocytes. Infectious agents such as malaria and babesiosis invade red blood cells. Disorders of red blood cell enzymes, membranes, and hemoglobin cause hereditary hemolytic anemias. Glucose-6-phosphate dehydrogenase deficiency leads to hemolysis in the presence of oxidative stress. Hereditary spherocytosis is characterized by spherocytes, a family history, and a negative direct antiglobulin test. Sickle cell anemia and thalassemia are hemoglobinopathies characterized by chronic hemolysis.
ABSTRACT: Chronic hepatitis C virus infection is a common and serious disease. Although an estimated 2.7 million persons in the United States have this disease, most have not yet been diagnosed. Recent advances in treatment provide successful cure in 50 to 80 percent of cases. Current drug therapy consists of a combination of pegylated interferon and ribavirin. Although all patients with chronic hepatitis C virus infection are potential candidates for treatment, pharmacologic therapy has a number of contraindications. Evaluation of suitability for treatment includes a thorough search for comorbid medical and psychiatric conditions that can be contraindications. Initial testing involves anti-hepatitis C virus antibodies, but definitive diagnosis of active disease requires detection of viral RNA. Most patients require a liver biopsy to determine the amount of hepatic fibrosis and ongoing hepatocellular inflammation. Viral genotype also should be determined: type 1 requires 12 months of treatment and does not respond as well as types 2 and 3, which require only six months of treatment. Common side effects of drug therapy include anemia, anorexia, depression, fatigue, fever, headache, myalgia, nausea, and erythema at the injection site.
Diagnosis of Acute Coronary Syndrome - Article
ABSTRACT: The term 'acute coronary syndrome' encompasses a range of thrombotic coronary artery diseases, including unstable angina and both ST-segment elevation and non-ST-segment elevation myocardial infarction. Diagnosis requires an electrocardiogram and a careful review for signs and symptoms of cardiac ischemia. In acute coronary syndrome, common electrocardiographic abnormalities include T-wave tenting or inversion, ST-segment elevation or depression (including J-point elevation in multiple leads), and pathologic Q waves. Risk stratification allows appropriate referral of patients to a chest pain center or emergency department, where cardiac enzyme levels can be assessed. Most high-risk patients should be hospitalized. Intermediate-risk patients should undergo a structured evaluation, often in a chest pain unit. Many low-risk patients can be discharged with appropriate follow-up. Troponin T or I generally is the most sensitive determinant of acute coronary syndrome, although the MB isoenzyme of creatine kinase also is used. Early markers of acute ischemia include myoglobin and creatine kinase-MB subforms (or isoforms), when available. In the future, advanced diagnostic modalities, such as myocardial perfusion imaging, may have a role in reducing unnecessary hospitalizations.