ITEMS IN AFP WITH MESH TERM:
Blood Cell Count
ABSTRACT: Back pain is fairly prevalent in healthy children and adolescents. When children or adolescents seek medical care for back pain, it is highly likely that underlying pathology will be identified. Common causes of back pain include nonspecific pain or muscle strain, herniated disk, spondylolysis, scoliosis, and Scheuermann's kyphosis. Less common causes include tumor, infection, and sickle cell crisis. If nonspecific back pain is suspected, treatment may include home-based exercise, physical therapy, or nonsteroidal anti-inflammatory drugs. If the history and physical examination suggest underlying pathology, radiography, complete blood count, erythrocyte sedimentation rate, and a C-reactive protein measurement should be performed. Follow-up magnetic resonance imaging, computed tomography, or bone scanning may be needed depending on the suspected cause. It is generally accepted that the following factors warrant immediate evaluation: patient age younger than four years, persistent symptoms, self-imposed activity limitations, systemic symptoms, increasing discomfort, persistent night-time pain, and neurologic symptoms.
ABSTRACT: Primary care physicians are often asked about easy bruising, excessive bleeding, or risk of bleeding before surgery. A thorough history, including a family history, will guide the appropriate work-up, and a physical examination may provide clues to diagnosis. A standardized bleeding score system can help physicians to organize the patient's bleeding history and to avoid overlooking the most common inherited bleeding disorder, von Willebrand's disease. In cases of suspected bleeding disorders, initial laboratory evaluations should include a complete blood count with platelet count, peripheral blood smear, prothrombin time, and partial thromboplastin time. More specialized yet relatively simple tests, such as the Platelet Function Analyzer-100, mixing studies, and inhibitor assays, may also be helpful. These tests can help diagnose platelet function disorders, quantitative platelet disorders, factor deficiencies, and factor inhibitors.
Evaluation of Macrocytosis - Article
ABSTRACT: Macrocytosis, generally defined as a mean corpuscular volume greater than 100 fL, is frequently encountered when a complete blood count is performed. The most common etiologies are alcoholism, vitamin B12 and folate deficiencies, and medications. History and physical examination, vitamin B12 level, reticulocyte count, and a peripheral smear are helpful in delineating the underlying cause of macrocytosis. When the peripheral smear indicates megaloblastic anemia (demonstrated by macro-ovalocytes and hyper-segmented neutrophils), vitamin B12 or folate deficiency is the most likely cause. When the peripheral smear is non-megaloblastic, the reticulocyte count helps differentiate between drug or alcohol toxicity and hemolysis or hemorrhage. Of other possible etiologies, hypothyroidism, liver disease, and primary bone marrow dysplasias (including myelodysplasia and myeloproliferative disorders) are some of the more common causes.
ABSTRACT: Atrial fibrillation is the most common cardiac arrhythmia. It impairs cardiac function and increases the risk of stroke. The incidence of atrial fibrillation increases with age. Key treatment issues include deciding when to restore normal sinus rhythm, when to control rate only, and how to prevent thromboembolism. Rate control is the preferred management option in most patients. Rhythm control is an option for patients in whom rate control cannot be achieved or who have persistent symptoms despite rate control. The current recommendation for strict rate control is a resting heart rate of less than 80 beats per minute. However, one study has shown that more lenient rate control of less than 110 beats per minute while at rest was not inferior to strict rate control in preventing cardiac death, heart failure, stroke, and life-threatening arrhythmias. Anticoagulation therapy is needed with rate control and rhythm control to prevent stroke. Warfarin is superior to aspirin and clopidogrel in preventing stroke despite its narrow therapeutic range and increased risk of bleeding. Tools that predict the risk of stroke (e.g., CHADS2) and the risk of bleeding (e.g., Outpatient Bleeding Risk Index) are helpful in making decisions about anticoagulation therapy. Surgical options for atrial fibrillation include disruption of abnormal conduction pathways in the atria, and obliteration of the left atrial appendage. Catheter ablation is an option for restoring normal sinus rhythm in patients with paroxysmal atrial fibrillation and normal left atrial size. Referral to a cardiologist is warranted in patients who have complex cardiac disease; who are symptomatic on or unable to tolerate pharmacologic rate control; or who may be candidates for ablation or surgical interventions.
Approach to Septic Arthritis - Article
ABSTRACT: Prompt diagnosis and treatment of infectious arthritis can help prevent significant morbidity and mortality. The acute onset of monoarticular joint pain, erythema, heat, and immobility should raise suspicion of sepsis. Constitutional symptoms such as fever, chills, and rigors are poorly sensitive for septic arthritis. In the absence of peripheral leukopenia or prosthetic joint replacement, synovial fluid white blood cell count in patients with septic arthritis is usually greater than 50,000 per mm3. Isolation of the causative agent through synovial fluid culture is not only definitive but also essential before selecting antibiotic therapy. Synovial fluid analysis is also useful to help distinguish crystal arthropathy from infectious arthritis, although the two occasionally coexist. Almost any microorganism can be pathogenic in septic arthritis; however, septic arthritis is caused by nongonococcal pathogens (most commonly Staphylococcus species) in more than 80 percent of patients. Gram stain results should guide initial antibiotic choice. Vancomycin can be used for gram-positive cocci, ceftriaxone for gram-negative cocci, and ceftazidime for gram-negative rods. If the Gram stain is negative, but there is strong clinical suspicion for bacterial arthritis, treatment with vancomycin plus ceftazidime or an aminoglycoside is appropriate. Evacuation of purulent material with arthrocentesis or surgical methods is necessary. Special consideration should be given to patients with prosthetic joint infection. In this population, the intraarticular cutoff values for infection may be as low as 1,100 white blood cells per mm3 with a neutrophil differential of greater than 64 percent.
ABSTRACT: One in 2,000 children younger than 18 years is thought to have a primary immunodeficiency disease. Antibody, combined B-cell and T-cell, phagocytic, and complement disorders are the most common types. Children with these diseases tend to have bacterial or fungal infections with unusual organisms, or unusually severe and recurrent infections with common organisms. A family history of primary immunodeficiency disease is the strongest predictor of a person having this type of disease. When an immunodeficiency disease is suspected, initial laboratory screening should include a complete blood count with differential and measurement of serum immunoglobulin and complement levels. The presence of lymphocytopenia on complete blood count suggests a T-cell disorder, whereas a finding of neutropenia suggests a phagocytic disorder. Abnormal serum immunoglobulin levels suggest a B-cell disorder. Abnormalities on assay of the classic or alternative complement pathways suggest a complement disorder. If laboratory results are abnormal, or if clinical suspicion continues despite normal laboratory results, children should be referred for further evaluation. Human immunodeficiency virus infection should also be considered, and testing should be performed, if appropriate; this infection often clinically resembles a T-cell disorder.