These methods offer similar or improved sensitivity to the thick blood film and require no specialized parasitologic expertise. Because these patients are usually treated with antimicrobial agents prior to obtaining specimens for bacterial cultures, some ophthalmologists favor culturing contact lens solution and cases. It should be noted that the total numbers of specimens tested in these studies are small but there is increasing evidence to the diagnostic value of NAAT in T. gondii retinitis [68–72]. With the exception of babesiosis, which may comprise as much as a third as many cases as Lyme borreliosis in some sites, these other tick-borne infections are relatively rare (a tenth as common as Lyme borreliosis). Did you know that upper respiratory tract infections are one of the leading causes of morbidity and mortality? Highly sensitive molecular assays for quantification of HCV RNA in serum or plasma (limit of detection of ≤25 IU/mL) are necessary to monitor patients’ virologic response and to determine cure (ie, sustained virologic response) from antiviral therapy. Borrelia burgdorferi–specific IgG and IgM scoring is based on the presence of at least 5 out of a possible 10 diagnostic IgG bands and 2 of a possible 3 IgM bands following reaching the threshold of a positive or equivocal screening EIA [248]. The potential list of causative agents of bone and joint infections is diverse and largely predicated on the nature and pathogenesis of infection and the host. Serology cannot distinguish between HSV-1 and HSV-2 unless a type-specific glycoprotein G–based assay is requested [195, 197]. As there are no FDA-cleared quantitative NAATs available for monitoring BK viral loads, each institution must establish a threshold for identifying patients at highest risk of BK virus–associated nephropathy. Positive IgG results do not differentiate past from current, active infection unless seroconversion is determined by testing acute and convalescent phase specimens. Specimens from private healthcare providers and institutions should be submitted to the local state health department laboratory (state, county, city) for appropriate processing. These procedures may include abbreviated identification of the organism, absence of susceptibility testing, and a comment that instructs the clinician to contact the laboratory if the culture result is thought to be clinically significant and requires additional workup and susceptibility results. Stool antigen tests have a reported sensitivity of 88%–98%, with sensitivity being higher in adults than in children. Chronic suppurative OM is associated with a higher rate of complications than acute OM. In comparison, the kinetoplast of T. brucei trypomastigotes is much smaller. This would let people test themselves and receive results at home for colds, flu, recurrent infections like those of the urinary tract (UTIs), and COVID-19. Both epidemiology and clinical presentation are used to narrow the organism(s) sought and the laboratory tests requested. Although an FDA-cleared multiplex PCR targeting 14 organisms is available for diagnosing meningitis and encephalitis, it should not be considered a replacement for culture since clinical experience with the assay is limited and specificity issues have been reported [17, 18]. Intraoperative frozen section analysis is a reliable diagnostic test. CHG is not recommended for use in infants <2 months of age but povidone-iodine followed by alcohol is recommended. Cytomegalovirus is a member of the Herpesviridae family and causes acute and latent infection. These times can be subject to change (e.g. Use anaerobic transport containers if anaerobes are suspected. Detection of Coccidioides antibody in CSF by immunodiffusion has lower specificity than complement fixation. Even when optimum handling occurs, cultures may fail to yield an organism. Photos and graphics subject to third party copyright used with permission or © Imperial College London. Similar to measles, mumps is considered eliminated in the United States, though travel-associated cases among unvaccinated individuals continue to occur, and while effective, the mumps vaccine has a protective rate of approximately 88% following administration of the 2 doses (www.cdc.gov/mumps/vaccination.html). Sampling of the burn wound by either surface swab or tissue biopsy for culture is recommended for monitoring the presence and extent of infection (Table 41). Acute bronchitis is largely due to viral pathogens and is less frequently caused by Mycoplasma pneumoniae and Chlamydia pneumoniae. This method only detects organisms colonizing the outside of the catheter, which is rolled onto an agar plate, after which the number of colonies is counted; organisms that may be intraluminal are missed. Older women with the following identified risk factors: inconsistent condom use, not in a monogamous relationship. A recent meta-analysis showed that the best predictors of an exudate were pleural fluid cholesterol level >55 mg/dL and an LDH >200 U/L or the ratio of pleural fluid cholesterol to serum cholesterol >0.3 [120]. Isolation of C. acnes may require culture incubation times as long as 14 days. Physicians should not demand that the laboratory report “everything that grows.” This can provide irrelevant information that could result in inaccurate diagnosis and inappropriate therapy. In this section infections are categorized as follows: cutaneous genital lesions, vaginitis and vaginosis, urethritis and cervicitis, and infections of the female pelvis, including endometritis and pelvic inflammatory disease (PID). Infectious agents associated with acute pancreatitis are numerous and diverse; however, superinfection of the pancreas is most often caused by gastrointestinal flora such as E. coli, Klebsiella spp, and other members of the Enterobacteriaceae, Enterococcus spp, Staphylococcus spp, Streptococcus spp, and Candida spp. Of the 4 antigenically distinct types, types 1 and 2 are most commonly associated with croup syndrome, while type 3 is associated most commonly with bronchiolitis and pneumonia.