The immune system functions to prevent and impede the local establishment or systemic dissemination of bacteria, viruses, fungi, and protozoa. This highly complex system has to recognize the pathogen, initiate inflammation, and generate antibodies and T-cell responses with the goal…
The coexistence of fever and rash suggests a relatively wide spectrum of pathologic entities for diagnostic consideration. This spectrum includes local or systemic infection with a wide range of microbial pathogens; toxin-mediated disorders, including those associated with bacterial superantigen production;…
Fever is a common symptom associated with a range of infectious and noninfectious etiologies. Two-thirds of all children visit a physician for fever before they reach the age of 2 years. The appropriate evaluation for fever depends on age, duration…
Hemostasis is a process that maintains normal blood flow through healthy vessels but, when a vessel is damaged, rapidly generates a platelet plug (primary hemostasis) and subsequent thrombin clot (secondary hemostasis) at the site of vascular injury. The major components…
Pancytopenia is defined by a decrease in all peripheral blood cell lines, including leukocytes, red blood cells (RBCs), and platelets. All of these cells are produced by the bone marrow, and therefore an evaluation of the bone marrow is often…
Pallor, a perceptible reduction in the usual color and tone of the skin and/or mucosa, is a highly nonspecific finding that may be a manifestation of a diversity of diseases or may be normal for a given individual. It may…
Given the role of the lymphatic system in developing adaptive responses to numerous antigenic challenges and the rate at which the immune system is exposed to novel antigens early in life, enlarged lymph nodes are regularly encountered both incidentally and…
It is estimated that up to 25% of the population reports the presence of joint hypermobility, but a quarter of the population does not have an associated connective tissue disorder, nor is the increased mobility deemed a health concern; nonetheless,…
The incidence of pediatric back pain increases with age and has a prevalence of nearly 40% by 18 years of age. While back pain is often related to overuse in sports, work, or a specific traumatic event, it may also…
Most gait disturbances are benign and resolve with normal growth and development. Others are pathologic in origin and necessitate treatment ( Table 45.1 ). TABLE 45.1 Causes of Gait Disturbances Mechanical Acute injuries (accidental or nonaccidental) Overuse conditions (mainly sports-related)…