Ceftriaxone for the treatment of febrile episodes in nonneutropenic patients with hematooncological disease or HIV infection: comparison of outpatient and inpatient care

BACKGROUND

Patients with hematooncological disease or HIV infection and febrile episodes are usually treated in hospital with broad-spectrum antibiotics. The aim of this observational study was to assess the feasibility of ambulatory parenteral antibiotic therapy in hematooncological or HIV-infected patients with confirmed or suspected infection.

METHODS

The results in an outpatient treatment group were compared with those obtained in a group initially treated in hospital. Data were gathered on 90 outpatients and 72 inpatients. The inclusion criteria were fever > or =37.5 degrees C with an identified focus of infection, fever > or =38.0 degrees C of suspected bacterial origin with no identified focus of infection, leukocytosis > or =9,000/microl or C-reactive protein elevation > or =10 mg/l.

RESULTS

Eighty outpatients and 69 inpatients were evaluable. Treatment in the outpatient group was begun with ceftriaxone. This led to defervescence in 87.5% of cases. The mean treatment duration was 7.1 days. Comparison of results in the outpatients with those initially hospitalized for treatment showed similar success rates. The mean hospital stay in the latter group was 12.9 days.

CONCLUSIONS

Ceftriaxone represents an effective treatment for outpatient management of febrile episodes in patients with hematooncological disease or HIV infection. Outpatient treatment is more cost-effective than inpatient care.

Relative contribution of day-to-day and intra-specimen variation in faecal egg counts of Schistosoma mansoni before and after treatment with praziquantel

There is evidence that faecal egg counts of Schistosoma mansoni vary considerably from day to day, which results in poor sensitivity of single stool readings. Intra-specimen variation of S. mansoni egg counts may also be considerable, but has previously been considered as the less important component. We quantified the relative contribution of these two sources of variation among 96 schoolchildren from an area in Cĵte d'Ivoire highly endemic for S. mansoni. Stool specimens were collected over 5 consecutive days, and 5 egg-counts were made in each specimen by the Kato-Katz technique. The point prevalence of the first sample was 42.7% and the cumulative prevalence after the maximum sampling effort was 88.5%. Using generalized linear mixed models we found that the presence of S. mansoni eggs in a stool sample varied much more between days than within specimens, indicating that stool sample examination over multiple days is required for accurate prevalence estimates. However, using the same approach, we found that among infected children intra-specimen variation in egg counts was 4.3 times higher than day-to-day variation. After praziquantel administration, day-to-day variation was more important than before, since most infections were very light and thus likely to be missed altogether by stool examination on a single day. We conclude that diagnostic sensitivity in high transmission areas is maximized by making several stool readings on several days, but examining 1 stool specimen several times can make reasonable estimates of infection intensity.

Mucin and phospholipids determine viscosity of gallbladder bile in patients with gallstones

AIM: An increased viscosity of gallbladder bile has been considered an important factor in the pathogenesis of gallstone disease. Besides lipids and proteins, mucin has been suggested to affect the viscosity of bile. To further clarify these issues we compared mucin, protein and the lipid componEnts of hepatic and gallbladder bile and its viscosity in patients with gallstones.

METHODS: Viscosity of bile (mPa.s) was measured using rotation viscosimetry in regard to the non Newtonian property of bile at low shear rates.

RESULTS: Biliary viscosity was markedly higher in gallbladder bile of patients with cholesterol (5.00 ± 0.60 mPa.s, mean ± SEM, n = 28) and mixed stones (3.50 ± 0.68 mPa.s; n = 8) compared to hepatic bile (0.92 ± 0.06 mPa.s, n = 6). A positive correlation between mucin and viscosity was found in gallbladder biles (r = 0. 65; P < 0.001) but not in hepatic biles. The addition of physiologic and supraphysiologic amounts of mucin to gallbladder bile resulted in a dose dependent non linear increase of its viscosity. A positive correlation was determined between phospholipid concentration and viscosity (r = 0.34, P < 0.005) in gallbladder biles. However, no correlation was found between total protein or the other lipid concentrations and viscosity in both gallbladder and hepatic biles.

CONCLUSION: The viscosity of gallbladder bile is markedly higher than that of hepatic bile in patients with gallstones. The concentration of mucin is the major determinant of biliary viscosity and may contribute by this mechanism to the role of mucin in the pathogenesis of gallstones.

Complex formation of Ni(II), Cu(II), Pd(II), and Co(III) with 1,2,3,4-tetraaminobutane

Complex formation of the two tetraamine ligands (2S,3S)-1,2,3,4-tetraaminobutane (threo-tetraaminobutane, ttab) and (2R,3S)-1,2,3,4-tetraaminobutane (erythro-tetraaminobutane, etab) with Co(III), Ni(II), Cu(II), and Pd(II) was investigated in aqueous solution and in the solid state. For Ni(II) and Cu(II), the pH-dependent formation of a variety of species [Mn(II)xLyHz](2x+z)+ was established by potentiometric titrations and UV/Vis spectroscopy. In sufficiently acidic solutions the divalent cations formed a mononuclear complex with the doubly protonated ligand of composition [M(H2L)]4+. An example of such a complex was characterized in the crystal structure of [Pd(H2ttab)Cl2]Cl2.H2O. If the metal cation was present in excess, increase of pH resulted in the formation of dinuclear complexes [M2L]4+. Such a species was found in the crystal structure of [Cu2(ttab)Br4].H2O. Excess ligand, on the other hand, lead to the formation of a series of mononuclear bis-complexes [Mq(HxL)(HyL)](q+x+y)+. The crystal structure of [Co(Hetab)2][ZnCl4]2Cl. H2O with the inert, trivalent Co(III) center served as a model to illustrate the structural features of this class of complexes. By using an approximately equimolar ratio of the ligand and the metal cation, a variety of polymeric aggregates both in dilute aqueous solution and in the solid state were observed. The crystal structure of Cu2(ttab)3Br4, which exhibits a two-dimensional, infinite network, and that of [Ni8(ttab)12]Br16.17.5H2O, which contains discrete chiral [Ni8(ttab)12]16+ cubes with approximate T symmetry, are representative examples of such polymers. The energy of different diastereomeric forms of such complexes with the two tetraamine ligands were analyzed by means of molecular mechanics calculations, and the implications of these calculations for the different structures are discussed.

pH-Dependent dissolving nano- and microparticles for improved peroral delivery of a highly lipophilic compound in dogs

RR01, a new highly lipophilic drug showing extremely low water solubility and poor oral bioavailability, has been incorporated into pH-dependent dissolving particles made of a poly(methacrylic acid-co-ethylacrylate) copolymer. The physicochemical properties of the particles were determined using laser-light-scattering techniques, scanning electron microscopy, high-performance liquid chromatography, and x-ray powder diffraction. Suspension of the free drug in a solution of hydroxypropylcellulose (reference formulation) and aqueous dispersions of pH-sensitive RR01-loaded nanoparticles or microparticles were administered orally to Beagle dogs according to a 2-block Latin square design (n = 6). Plasma samples were obtained over the course of 48 hours and analyzed by gas chromatography/mass spectrometry. The administration of the reference formulation resulted in a particularly high interindividual variability of pharmacokinetic parameters, with low exposure to compound RR01 (AUC0-48h of 6.5 microg x h/mL and coefficient of variation (CV) of 116%) and much higher Tmax, as compared to both pH-sensitive formulations. With respect to exposure and interindividual variability, nanoparticles were superior to microparticles (AUC0-48h of 27.1 microg x h/mL versus 17.7 microg x h/mL with CV of 19% and 40%, respectively), indicating that the particle size may play an important role in the absorption of compound RR01. The performance of pH-sensitive particles is attributed to their ability to release the drug selectively in the upper part of the intestine in a molecular or amorphous form. In conclusion, pH-dependent dissolving particles have a great potential as oral delivery systems for drugs with low water solubility and acceptable permeation properties.

Platelet-associated tissue factor contributes to the collagen-triggered activation of blood coagulation

The extravascular localization of tissue factor (TF), the central initiator of coagulation, is thought to ensure that thrombus formation is prevented in the intact vessel. We observed that during a 5-min stimulation of human blood with collagen (type I), TF antigen appeared on the surface of platelets adhering to leukocytes. The rapidly presented intravascular TF was competent to start the coagulation cascade. The isolated platelets from healthy donors contained appreciable amounts of the TF protein, while no TF antigen was detected in the neutrophils and rapidly isolated monocytes. Direct interactions with the neutrophils and monocytes were apparently necessary to activate the platelet-associated TF. This was most likely mediated by inactivation of tissue factor pathway inhibitor through leukocyte elastase. In summary, the leukocyte-elicited activation of the platelet TF participates in the rapid initiation of coagulation by collagen.

Comparison of effects of clopidogrel versus ticlopidine on platelet function in patients undergoing coronary stent placement

Clopidogrel in combination with aspirin administered as a loading dose of 450 mg reveals an accelerated antiplatelet effect in the early hours after first administration in patients undergoing coronary stent placement.

Differential antiplatelet effects of various glycoprotein IIb-IIIa antagonists

The blockade of platelet glycoprotein IIb-IIIa (GPIIb-IIIa) was recently introduced as a new antiplatelet strategy. At present, various GPIIb-IIIa inhibitors are available to treat patients with acute coronary syndrome or when undergoing percutaneous coronary interventions. The current study systematically evaluates the antiplatelet effects of GPIIb-IIIa inhibitors in clinical use. Using conformation-dependent monoclonal antibodies [ligand-induced binding sites (LIBS-1), PMI-1] and flow cytometry, we showed that the GPIIb-IIIa antagonists abciximab, integrelin, lamifiban, and tirofiban, but not EMD 122347 or YM 337, induced LIBS activity of platelet GPIIb-IIIa. The LIBS activity of GPIIb-IIIa antagonists correlates with a proaggregatory response of fixed platelets pretreated with GPIIb-IIIa antagonists (intrinsic activity). All tested GPIIb-IIIa antagonists completely inhibit concentration-dependent ADP (20 micromol/l)-induced aggregation. In contrast, substantial TRAP (25 micromol/l)-induced platelet aggregation still occurs even at high inhibitor concentrations of the tested GPIIb-IIIa antagonists. In addition, we show that GPIIb-IIIa antagonists are poor inhibitors of platelet release reaction (ATP and P-selectin secretion) especially when strong agonists such as TRAP are used to activate platelets. Inhibition of platelet procoagulant activity (thrombin generation) by GPIIb-IIIa antagonists is dependent on the type and concentration of antagonists and on the strength of stimulus (thrombin, tissue factor) used to induce platelet-dependent thrombin generation. The present data show that significant pharmacological differences exist between GPIIb-IIIa antagonists that may have consequences for antithrombotic strategies and for future drug development.

Associations of peak shifts in age--prevalence for human malarias with bednet coverage

Effects of bednet coverage (C) on prevalence of malaria were analysed using data from 1990-92 from 9 Papua New Guinean villages. Effects of coverage varied by age, resulting in a shift in age of peak prevalence from 4.7 (C = 0%) to 11.6 (C = 100%) years for Plasmodium falciparum, from 3.4 to 4.9 years for P. vivax and from 11.0 to 16.8 years for P. malariae. In small areas with no bednets the age distribution of P. falciparum parasitaemia was like that of a holoendemic area. Where coverage was complete the pattern corresponded to mesoendemicity. Thus, protracted use of bednets can result in profound changes in the endemicity of malaria even when coverage is incomplete and without insecticide treatment. Average entomological inoculation rates (EIRs) estimated from indoor landing rates on individuals without bednets were 35, 12 and 10 infectious bites per person per annum for P. falciparum, P. vivax and P. malariae, respectively. Logistic regression analyses indicated that the EIR estimate for P. falciparum was related to prevalence of this species independently of effects of bednet coverage. However, the recent EIR still accounted for much less variation than did the bednets. A similar pattern was seen for P. malariae, while there were no significant relationships between the recent EIR and the parasite positivity for P. vivax. It is concluded that short-term variations in inoculation rate are not important determinants of parasite prevalence in this population.

Differential effects of hypoxia on untreated and NGF treated PC12 cells

Perinatal hypoxia is known to induce long-lasting changes in the central dopaminergic system. In order to understand the cellular mechanism of these changes, we studied the effects of hypoxia on the levels of dopamine (DA) and tyrosine hydroxylase (TH) mRNA in untreated and NGF treated PC12 cells. On the second day after plating (DAP), cells were exposed to a hypoxic episode (pO2 = 10-20 mm Hg, 24 h), and the levels of DA and TH mRNA were examined on DAP 4 and DAP 8. In untreated cells, hypoxia induced a two fold increase both in DA and TH mRNA levels on DAP 4 which normalized up to DAP 8. This increase correlated with an activation of the hypoxia inducible factor (HIF-1alpha), measured with a reporter gene. In contrast, NGF treated cells responded to hypoxia with an increase of DA level on DAP 8. In these cells neither an increase of the HIF-1alpha activity measured immediately after hypoxia nor a significant increase of the TH mRNA level on DAP 8 were found. The findings indicate that NGF shifts the hypoxia induced changes of DA levels from a short-term to a long-term mode. The long-term increase of dopamine levels is the most likely result of changes connected with cell growth and differentiation and not the result of a long-term TH mRNA level increase.

Composition and immunofluorescence studies of biliary "sludge" in patients with cholesterol or mixed gallstones

BACKGROUND/AIMS

Gallbladder bile from patients with cholesterol or mixed gallstones frequently contains biliary "sludge", a suspension of cholesterol monohydrate crystals and pigment granules embedded in mucin and proteins. The composition of biliary "sludge" and the preferential localization of mucin and proteins could be an indicator for its potential role in gallstone formation.

METHODS

Ultracentrifugation (100000 g/l h) was used to precipitate "sludge" from bile, and the concentration difference of its main components between native bile and ultracentrifuged bile samples was calculated. After purification of the sediment, immunolocalization was performed for the detection of mucin, IgA, albumin, aminopeptidase, and anionic polypeptide fraction using polyclonal and monoclonal antibodies.

RESULTS

The amount of sludge in gallbladder bile was 4.26 mg/ml-0.78 (mean+/-SEM) in patients with cholesterol and 2.51 mg/ml+/-0.39 in patients with mixed stones and cholesterol was the main component (48.9+/-4.6% and 44.4+/-7.1%). The sediment appeared as a mixture of vesicular aggregates and pigment particles which were linked by a gel matrix of mucin containing cholesterol crystals. While anionic polypeptide fraction and aminopeptidase were associated to pigments, IgA was uniformly spread in the crystalline parts of "core-like" structures, and albumin, when it was present, appeared as randomly located small spots.

CONCLUSIONS

Our study demonstrates that the cholesterol content and the distribution pattern of mucin and different proteins is similar in the sediments of biliary "sludge" to that previously shown in cholesterol and mixed gallstones. This suggests that biliary "sludge" represents an early stage of gallstone formation in these patients.

Perinatal asphyxia induces region-specific long-term changes in mRNA levels of tyrosine hydroxylase and dopamine D(1) and D(2) receptors in rat brain

To study the effects of neonatal asphyxia on gene expression of the dopaminergic systems, we determined quantitatively the mRNA levels of tyrosine hydroxylase, dopamine transporter, dopamine D(1) and D(2) receptors in substantia nigra/ventral tegmental area, striatum and limbic area. The mRNA levels were determined at one and 4 weeks after asphyxia by a quantitative reverse transcription polymerase chain reaction method. Spontaneously and Caesarean section born rats showed similar mRNA levels with the exception of an increase of tyrosine hydroxylase mRNA levels in the limbic area of 4-week-old animals. Five min of asphyxia did not change the mRNA levels in any region compared to that in the spontaneously born rats. Fifteen and twenty min of asphyxia induced region-specific alterations in mRNA levels. In SN/VTA an increase of tyrosine hydroxylase mRNA levels in the 1-week-old rats and in striatum an increase of D(1) and D(2) dopamine receptor mRNA levels in the 4-week-old rats were observed. Fifteen min of asphyxia induced a selective increase of D(1) and D(2) dopamine receptor mRNA levels in the limbic area of 4-week-old rats. These observations indicate that neonatal asphyxia triggers a cascade of gene expressions for tyrosine hydroxylase and D(1) and D(2) dopamine receptors. In 1-week-old rats, the gene expression of tyrosine hydroxylase increased in the cell body region substantia nigra/ventral tegmental area. This change may increase the D(1) and D(2) dopamine receptor expression in the target regions striatum and limbic area during further development.

Incomplete inhibition of platelet aggregation and glycoprotein IIb-IIIa receptor blockade by abciximab: importance of internal pool of glycoprotein IIb-IIIa receptors

Resting platelets contain a substantial internal pool of GPIIb-IIIa complexes that is exposed on the surface of activated platelets. Whether the exposure of internal GPIIb-IIIa complexes on the activated platelet surface affects therapy with GPIIb-IIIa antagonists is poorly understood. We addressed this issue in thirteen patients who underwent elective coronary stenting and received abciximab. Platelet aggregation, surface expression of GPIIb-IIIa and P-selectin, receptor blockade of GPIIb-IIIa, and platelet release in response to ADP and thrombin-receptor activating peptide (TRAP) were determined ex vivo by Lumi-aggregometry and flow cytometry before, during and after abciximab administration. We found that inhibition of aggregation and GPIIb-IIIa blockade of ADP-stimulated platelets was almost complete during abciximab administration. In contrast, when TRAP was used to stimulate platelets ex vivo aggregation was only partially inhibited, most likely due to release of internal pool of unblocked GPIIb-IIIa complexes. Using electron microscopy we found that 7E3-occupied GPIIb-IIIa complexes are internalized into the surface connected system (SCS) and the alpha-granules of washed platelets which was associated with a reduced degranulation of the alpha-granula membrane protein P-selectin. We conclude, that despite internalization of abciximab into the internal pool of GPIIb-IIIa, upon strong platelet activation with thrombin a significant amount of unblocked internal GPIIb-IIIa can be exposed on the platelet surface and mediate platelet aggregation. Incomplete blockade of the internal GPIIb-IIIa pool may limit clinical efficacy of abciximab.

Bronchopulmonary and mediastinal leishmaniasis: an unusual clinical presentation of Leishmania donovani infection

We describe a case of unusual leishmaniasis in a Sudanese man with a history of progressively enlarging granulomatous mediastinal lymphadenopathy, worsening hemoptysis, and an intense mucosal granulomatous inflammatory response in the large bronchi. Leishmania donovani DNA was detected in bronchial biopsies by polymerase chain reaction. This is a novel description of human leishmanial infection in an immunocompetent patient involving this anatomical site. The patient's condition improved clinically, spirometrically, and radiologically after a course of treatment with amphotericin B. The cell-mediated immune response was analyzed before, during, and after successful antileishmanial chemotherapy.

[2 benign bone lesions in a tubular bone: misinterpretation of clinical and radiological findings]

INTRODUCTION

Bone lesions are common at puberty. Most of them are detected by chance at examination for other reasons. The nonossifying fibroma does not produce any clinical symptoms and normally is diagnosed by chance. A spontaneous healing is discussed. The osteoid osteoma is characterized by its nocturnal pain and relief of pain at therapy with salicylates. Operative procedures are indicated for healing.

CASE

A 12-year-old girl presented with radiological signs of a nonossifying fibroma. Because of local radionuclid uptake and clinical symptoms an operative procedure was carried out. Postoperative remaining pain resulted in radiological detection of a nearby osteoid osteoma and local operative therapy.

CONCLUSION

Two benign bone lesions at one tubular bone are an extremely rare situation. The clinical symptoms and the radionuclid uptake are misinterpretated and falsely assigned to the nonossifying fibroma. All clinical symptoms and radiological signs have to be correlate correctly with the diagnosis and consecutive therapy in order to avoid a misinterpretation of obvious clear radiological results.

Serological response to Helicobacter pylori recombinant antigens in Chilean infected patients with duodenal ulcer, non-ulcer dyspepsia and gastric cancer

We have previously cloned 10 Helicobacter pylori antigen genes from a Chilean strain including: cytotoxin VacA, a truncated region of CagA (called A17), a species-specific protein (Ag26), urease subunits (UreA, UreB), a flagellin, (FlaB), heat shock proteins (HspA and HspB), an adhesin (HpaA) and a lipoprotein (Lpp20). Immunogenicity of these antigens was tested by immunoblot with sera of Chilean infected patients, revealing that HpaA, A17, HspB and VacA were more frequently recognized (86%, 82%, 68% and 68%, respectively). According to the clinical condition, it was determined that Lpp20 was preferentially recognized by sera from non-ulcer dyspepsia patients (80%), A17 and VacA by patients with duodenal ulcer (92% and 83% respectively), and HspB by patients with duodenal ulcer (83%) and gastric cancer (90%). An ELISA was developed with a purified mixture of A17 and VacA antigens to test the different groups of patients. It was found that sera from duodenal ulcer patients showed higher values than those from non-ulcer dyspepsia patients, but this difference was not significant (p<0.2). Moreover, sera from gastric cancer patients showed values lower than those from non-ulcer dyspepsia patients (p<0.019). These results indicate that, in the Chilean population, antibodies raised against VacA and A 7 are not markers either for duodenal ulcer or for gastric cancer.