Infection imaging studies

Imaging studies also may help to identify anatomic localization of the infection. These studies usually are performed in conjunction with other tests to establish or rule out the presence of an infection. X-rays are performed commonly to establish the diagnosis of pneumonia, as well as the severity of disease (single versus multilobe involvement). CT scans are a type of x-ray that produces a three-dimensional image of the combination of soft tissue, bone, and blood vessels. In contrast, MRI use electromagnetic radio waves to produce two- or three-dimensional images of soft tissue and blood vessels with... 

Pomara N, Crandall DT, Choi SJ, Johnson G, Lim KO (2001) White matter abnormalities in HIV-1 infection A diffusion tensor imaging study. Psychiatry Res 106 15-24. 

Stout JC, EUis RJ, Jemigan TL, Archibald SL, Abramson 1, Wolfson T, McCutchan JA, Wallace MR, Atkinson JH, Grant I, HIV Neurobe-havioral Research Center Group (1998) Progressive cerebral volume loss in human immunodeficiency vims infection A longitudinal volumetric magnetic resonance imaging study. Arch Neurol 55 161-168. 

Hepatosplenic candidiasis—Clinical presentation often manifested only as fever while a patient remains neutropenic (<1000 WBC/ mm ). When the WBC count increases to >1000 cells/mm, imaging studies can detect the presence of abscess or microabscesses in the liver and spleen, often found with acute suppurative and granulomatous reactions. Infection may persist for months and ultimately cause the patient s death despite aggressive systemic therapy with antifungal agents. Also known as chronic systemic candidiasis. 

HIV infection Imaging was used in an open study for 10 weeks in 15 subjects with human immunodeficiency virus (HIV) and evidence of cognitive decline there was no evidence of improvement in either cognition or mood [3 ]. 

Hoberman A, Charron M, Hickey RW, Baskin M, Kearney DH, Wald ER (2003) Imaging studies after a first febrile urinary tract infection in young children. N Engl J Med... 

Distinction should be made between monosymptomatic enuresis nocturna and incontinence. Patients with persistent and severe monosymptomatic enuresis nocturna despite treatment should undergo kidney and bladder ultrasound and VCU as well, if there are positive ultrasound findings and/or a history of urinary tract infection. In wetting children (daytime with or without nighttime urinary incontinence) with urinary tract infection with/without urge, kidney and bladder ultrasound and a VCU have to be performed as well. Assessment of potential stool retention has to be part of the imaging studies. 

The same liposomal preparation was used to investigate the effect of the administered dose on the biodistribution and pharmacokinetics (41). The effect of the lipid dose of Tc-HYNIC-PEG-liposomes was investigated in the low-dose range (0.02-1.0 pmol/kg), typically for noninvasive imaging applications. The biodistribution and pharmacokinetics of "Tc-HYNIC-PEG-liposomes at various dose levels were studied in rats and rabbits with a focal Escherichia coli infection. Moreover, the pharmacokinetics of Tc-HYNIC-PEG-liposomes at two lipid dose levels were studied in four patients. In rabbits, enhanced clearance was observed at a dose level of 0.02 pmol/kg. The circulatory half-life decreased from 10.4 to 3.5 hours (at 1.0 and 0.02 pmol/kg, respectively). At the lowest dose level, liposomes were mainly taken up by the liver and to a lesser extent by the spleen. Most importantly, the rapid clearance of low-dose PEG liposomes was also observed in humans when relatively low lipid doses were administered as is shown in Figure 4. This study showed that, at very low lipid doses, the biodistribution of PEG liposomes is dramatically altered. 

Foetal mesencephalic tissue has been implanted in the striatum of patients with the juvenile form of Parkinson s disease and has been shown to develop functional axons this has enabled the dose of L-dopa to be reduced. Both imaging and pharmacological studies have now shown that functional dopaminergic neurons can develop in the brain of the patient following tissue transplantation. However, a major ethical objection has been raised to such transplants as six to seven foetal brains are required to obtain sufficient tissue. In addition, only about 20% of neurons survive transplantation. The ethical problem may be overcome by using brain transplants from domestic animals such as pigs. Such xenotransplants have been shown to survive in the human brain but the main problem with the extensive use of such transplants is the possible spread of viruses and prion infections. 

The liver function was also studied in patients with viral hepatitis. During the acute phase of the infection, the ASGP-receptor concentration was markedly decreased, but during the course of the disease receptor concentrations increased to normal values. This correlated well with other laboratory tests for liver function and thus again demonstrates the potential of this imaging technique in evaluating the condition of patients with acute viral hepatitis [271],... 

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