laminaran and Fever

A 59-year-old patient with multiple myeloma on maintenance chemotherapy presented with fever, weight loss, and night sweats. An F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) computed tomography (CT) showed intra-abdominal lymphadenopathy with a mesenteric mass that led to further workup and diagnosis of histoplamosis. The patient was treated with amphotericin B and subsequently switched to itraconazole. This exemplifies the usefulness of FDG PET CT in diagnosis of infectious complications.

Topics: Amphotericin B; Antifungal Agents; Antineoplastic Agents; beta-Glucans; Colonoscopy; Fever; Fluorodeoxyglucose F18; Gastrointestinal Diseases; Hematopoietic Stem Cell Transplantation; Histoplasma; Histoplasmosis; Humans; Ileum; Intestinal Obstruction; Itraconazole; Lymphadenopathy; Male; Middle Aged; Multiple Myeloma; Positron-Emission Tomography; Radiopharmaceuticals; Tomography, X-Ray Computed; Weight Loss

The desert locust Schistocerca gregaria behaviorally thermoregulates in order to try and maintain a favoured "set point" body temperature. Locusts infected with the deuteromycete fungal pathogen Metarhizium anisopliae var acridumchoose a significantly elevated temperature. This "behavioral fever" greatly delays the progress of mycosis. We have confirmed this phenomenon and shown that desert locusts also fever when infected with the bacterial pathogen Serratia marcescens. Elevation in the prefered environmental temperature occurs also upon injection with laminarin and lipopolysaccharide (microbial cell wall components). Since such treatments also stimulate the immune system it would appear that "behavioral fever" is probably a feature of the immune response. The eicosanoid biosynthesis inhibitor dexamethasone prevented laminarin invoked fever. This effect was reversable by arachidonic acid. Therefore in common with the febrile response in mammals behavioral fever in insects may be mediated locally by circulating eicosanoids.

Topics: Animals; Body Temperature Regulation; Dexamethasone; Eicosanoids; Fever; Glucans; Grasshoppers; Male; Mitosporic Fungi; Mycoses; Polysaccharides; Serratia Infections; Serratia marcescens; Time Factors

We developed a new quantitative system for diagnosis of invasive pulmonary aspergillosis (IPA) using real-time automated polymerase chain reaction (PCR). Intra-assay and interassay precision rates for in vitro examination were 2.53% and 2.20%, respectively, and the linearity of this assay was obtained when there were >20 copies/well. We examined 323 samples taken from 122 patients with hematological malignancies, including 33 patients with IPA and 89 control patients. Blood samples were subjected to PCR antigen detection methods, using enzyme-linked immunosorbent assay (ELISA) and determination of plasma (1-->3)-beta-D-glucan (BDG) concentration. The sensitivities of PCR, ELISA, and BDG measurement for diagnosis of IPA were 79%, 58%, and 67%, respectively; the specificities were 92%, 97%, and 84%. Positive findings on PCR preceded those of computed tomography by -0.3+/-6.6 days, those of BDG measurement by 6.5+/-4.9 days, and those of ELISA by 2.8+/-4.1 days. Real-time PCR was sensitive for IPA diagnosis, and quantitation was accurate.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aspergillosis; Aspergillus; beta-Glucans; Enzyme-Linked Immunosorbent Assay; Female; Fever; Glucans; Humans; Lung Diseases, Fungal; Male; Middle Aged; Polymerase Chain Reaction; Reproducibility of Results; Sensitivity and Specificity; Time Factors; Tomography, X-Ray Computed

(1-->3)-beta-D-glucan is a characteristic fungal cell-wall constituent. To assess the clinical usefulness of this glucan in screening for invasive fungal infection or fungal febrile episodes, we measured the plasma concentration at the time of routine blood culture in 202 febrile episodes by means of factor G, a horseshoe-crab coagulation enzyme that is extremely sensitive to this polysaccharide. With a plasma cut-off value of 20 pg/mL, 37 of 41 episodes of definite fungal infections (confirmed at necropsy or by microbiology) had positive results (sensitivity 90%). All of 59 episodes of non-fungal infections, tumour fever, or collagen diseases had concentrations below the cut-off value (specificity 100%). Of 102 episodes of fever of unknown origin, 26 had plasma glucan concentrations of more than 20 pg/mL. With those 102 cases taken as non-fungal infections, the positive predictive value of the test was estimated as 59% (37/63), the negative predictive value as 97% (135/139), and the efficiency as 85% (172/202). The positive predictive value should improve if there were a sensitive gold standard that could discriminate fungal from non-fungal infections. Causative fungi included candida, aspergillus, cryptococcus, and trichosporon. Determination of plasma (1-->3)-beta-D-glucan with factor G is a highly sensitive and specific test for invasive deep mycosis and fungal febrile episodes, and will substantially benefit immunocompromised patients.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aspergillosis; beta-Glucans; Blood Coagulation Factors; Candidiasis; Child; Child, Preschool; Female; Fever; Fungemia; Glucans; Humans; Male; Middle Aged; Mycoses; Sensitivity and Specificity; Serine Endopeptidases