Since the first cases of acquired immunodeficiency syndrome (AIDS) were reported in the United States in 1981, surveillance case definitions for human immunodeficiency virus (HIV) infection (the cause of AIDS) and AIDS have undergone several revisions to respond to diagnostic advances. Continue reading
The Berlin definition, proposed in 2012, breaks with tradition by establishing three risk strata that are based on the degree of hypoxemia as assessed at a minimum positive end-expiratory pressure (PEEP).
Clostridium difficile ( C. difficile ) is a Gram-positive, sporeforming bacterium usually spread by the fecal-oral route. It is non-invasive and produces toxins A and B that cause disease, ranging from asymptomatic carriage, to mild diarrhea, to colitis, or pseudomembranous colitis. CDI is defined as the acute onset of diarrhea with documented toxigenic C. difficile or its toxin and no other documented cause for diarrhea.
Early recognition is critical for infection control. Healthcare providers should be alert for and evaluate any patients suspected of having EVD.
In 2004, the ADQI group and representatives from three nephrology societies established the Acute Kidney Injury Network (AKIN). Its intentions are to facilitate international, interdisciplinary and intersocietal collaborations and to ensure progress in the field of AKI, including the development of uniform standards for the definition and classification of AKI. As part of this process, the RIFLE nomenclature and classification was modified to a staging/classification system differentiating between AKI stage I, II and III. In addition, a 48-hour time window for the diagnosis of AKI was introduced to ensure that the process was acute.
1996 Case Definition
Hemolytic uremic syndrome (HUS) is characterized by the acute onset of microangiopathic hemolytic anemia, renal injury, and a low platelet count. Thrombotic thrombocytopenic purpura (TTP) also is characterized by these features but can include central nervous system (CNS) involvement and fever and may have a more gradual onset. Most cases of HUS (but few cases of TTP) occur after an acute gastrointestinal illness (usually diarrheal).
Bartter’s syndrome is a rare disease that most often presents in the neonatal period or early childhood with polyuria, polydipsia, salt craving, and growth retardation. Blood pressure is normal or low. Metabolic abnormalities include hypokalemia, hypochloremic metabolic alkalosis, decreased urinary concentrating and diluting ability, hypercalciuria with nephrocalcinosis, mild hypomagnesemia, and increased urinary prostaglandin excretion.
After identification of novel influenza A (H1N1) virus infection in Mexico, a case definition was developed. The initial definition of suspected novel influenza A (H1N1) virus infection included any hospitalized patient with severe acute respiratory illness. On May 1, 2009, this definition was expanded to include any person with acute respiratory illness defined as fever and either sore throat or cough. On May 11, 2009, the definition of suspected case was changed again to include any person with:
Syphilis is a complex sexually transmitted disease that has a highly variable clinical course. Classification by a clinician with expertise in syphilis may take precedence over the following case definitions developed for surveillance purposes.
I. Streptococcal TSS
A. Isolation of group A Streptococcus
1. From a sterile site
2. From a nonsterile body site
B. Clinical signs of severity
2. Clinical and laboratory abnormalities (requires two or more of the following):
a) Renal impairment
c) Liver abnormalities
d) Acute respiratory distress syndrome
e) Extensive tissue necrosis, i.e., necrotizing fasciitis
f) Erythematous rash