Case report of a giant cell tumor of the carotid sheath

Giant cell tumor of the soft tissue (GCTST) is a neoplasm with low malignant potential and typically affects the trunk and extremities. Herein, we present a case of a palpable right neck mass diagnosed as a GCTST of the carotid sheath in a 38-year-old woman. A review of the imaging characteristics as well as of the differential diagnoses of primary neoplasms of the carotid space is presented.

Risky sexual behaviors reported by patients in a free sexual health center in Paris (2017-2020)

Background

In France, a national network of free sexual health centers offers prevention, diagnosis and treatment for STI and HIV. These centers help socially disadvantaged and high-risk populations to access STI/HIV testing but few detailed data are available on patients' sexual behaviors. This study aims to describe sexual behaviors among attendees of a Parisian free sexual health center for STI/HIV screening.

Methods

This observational study included 5130 patients who attended the center for STI/HIV testing from August 2017 through January 2020 and completed a self-administered electronic questionnaire. Data obtained from the consultation database and the questionnaire included STI results, sociodemographic characteristics and sexual behaviors. Criteria reported in the literature to define “high-risk sexual behavior (HRSB)” were used to describe sexual practices.

Results

Median age of patients was 26 years [Q1-Q3:23-32] and 8% had no health insurance. Slightly less than one third of patients were women who had sex with men, 37% were men who had sex exclusively with women and 18% were men who had sex with men; 22% had never had HIV testing before the consultation. Regarding sexual practices, 76% reported unprotected sexual intercourse, 3% transactional sex and 8% a history of sexual violence. Depending on the threshold used to define multiple partners (≥6 vs ≥ 2 partners during the previous year), the proportion of patients varied from 31% to 81%. Globally, the proportion of patients reporting at least one HRSB ranged from 87% to 95%. Eleven percent of patients had at least one STI (mostly chlamydia).

Conclusions

Our sexual health center fulfills its missions as most patients consulting for STI/HIV testing reported HRSB and almost one quarter had never previously had an HIV test. The next step will be to explore profiles including sexual behavior, sociodemographic characteristics and HIV knowledge to adapt our prevention strategy to patients' needs.

Key messages

Our sexual health center fulfills its missions as most patients consulting for STI/HIV testing reported HRSB and almost one quarter had never previously had an HIV test. The next step will be to explore profiles including sexual behavior, sociodemographic characteristics and HIV knowledge to adapt our prevention strategy to patients’ needs.

[Knowledge and experience of 2- to 15-year-old children's parents consulting in pediatric emergency departments for asthma]

INTRODUCTION

This study aimed at assessing parents' knowledge and perception in relation to their child's condition when arriving at the emergency ward following an asthma attack. The overall objective was to determine how parent education could be improved.

MATERIALS AND METHODS

This study was conducted over 9 months as a multicenter descriptive and qualitative study based on a self-administered questionnaire for parents of asthmatic children, aged 2-15 years.

RESULTS

The questionnaire was delivered to 88 children out of 1472 (6%). Approximately 69% of the children included in the study presented with partially controlled or uncontrolled asthma. Fifty percent of the patients were insufficiently monitored and without therapy. Half of the parents said they had never received any information concerning their child's condition. The majority (86%) did not know the basic cause of the disease, 30% percent were unable to detect the features of clinical exacerbation, and 17% were not using an adequate emergency protocol. The illness experience was relatively easy for two-thirds of the children and the parents' perceptions were in line in 50% of the cases.

DISCUSSION

Knowledge of parents and their children suffering from asthma is insufficient for optimal control and disease management. Instructions on detecting the signs of asthma severity as well as the establishment of an individualized emergency protocol and medical follow-up should be of prime concern and could reduce emergency department use.

CONCLUSION

Doctors have a key role to play in educating and explaining disease characteristics to patients and their families. Therapeutic education also needs to be intensified.

Co-activation of VTA DA and GABA neurons mediates nicotine reinforcement

Smoking is the most important preventable cause of mortality and morbidity worldwide. This nicotine addiction is mediated through the nicotinic acetylcholine receptor (nAChR), expressed on most neurons, and also many other organs in the body. Even within the ventral tegmental area (VTA), the key brain area responsible for the reinforcing properties of all drugs of abuse, nicotine acts on several different cell types and afferents. Identifying the precise action of nicotine on this microcircuit, in vivo, is important to understand reinforcement, and finally to develop efficient smoking cessation treatments. We used a novel lentiviral system to re-express exclusively high-affinity nAChRs on either dopaminergic (DAergic) or γ-aminobutyric acid-releasing (GABAergic) neurons, or both, in the VTA. Using in vivo electrophysiology, we show that, contrary to widely accepted models, the activation of GABA neurons in the VTA plays a crucial role in the control of nicotine-elicited DAergic activity. Our results demonstrate that both positive and negative motivational values are transmitted through the dopamine (DA) neuron, but that the concerted activity of DA and GABA systems is necessary for the reinforcing actions of nicotine through burst firing of DA neurons. This work identifies the GABAergic interneuron as a potential target for smoking cessation drug development.

[Polymorphic expression of epilepsy and cognitive impairment in ring chromosome 20 syndrome]

Ring chromosome 20 syndrome combines epilepsy with varying levels of mental retardation, behavioral disorders, and malformations. Epilepsy is generally serious, with frequent drug resistance. The pathophysiology of seizures remains unclear. Rearrangements of two epilepsy genes, CHRNA4 and KCNQ2, have been raised as the cause. We report the observation of one child, with a telomeric deletion 20p13, with no epileptic symptoms. Preservation of CHRNA4 and KCNQ2 gene activity could explain this distinctive feature.

Esophageal cancer in a young woman with bulimia nervosa: a case report

Adenocarcinoma of the esophagus has increased dramatically within the United States and continues to have a poor prognosis despite aggressive treatment. Identifying potential risk factors is critical for the early detection and treatment of this disease. The present case report describes a very young woman who developed adenocarcinoma of the esophagus after only a brief history of bulimia. These findings suggest that even in very young patients, bulimia may represent a risk factor for adenocarcinoma of the esophagus.

Statut vaccinal d'enfants ayant un antécédent de convulsion ou d'épilepsie débutante : étude rétrospective comparative réalisée au CHU de Bordeaux

Vaccination is a common act in medicine. Some serious side effects are always feared in a preventive action, mainly among high-risk patients such as epileptic children or children having already experienced a seizure.

OBJECTIVES

To study consequences of such background on the vaccine medical practice.

POPULATION AND METHODS

A retrospective study comparing the vaccine statute of children with or without case history of seizures was carried out by the neurologic and paediatric emergencies departments. The study compared 55 with seizures versus 109 without.

RESULTS

On the whole, the 2 groups were insufficiently vaccinated. A statistically significant difference was highlighted between the 2 groups for the vaccination coverage by vaccine DTP (diphtheria-tetanus-pertussis) (P=0.017) and MMR (measles-mumps-rubella) (P=0.004). However, concerning the vaccination against hepatitis B, no difference was found.

CONCLUSION

The usual contra-indications of these vaccines do not explain this difference and progress must be made to improve the vaccination coverage of epileptic children.

Primary Ductal Adenocarcinoma of the Lacrimal Gland

OBJECTIVE

To report the case of a 59-year-old man with a right lacrimal gland mass, subsequently diagnosed as primary ductal adenocarcinoma of the lacrimal gland.

DESIGN

Interventional case report.

METHODS

We report the clinical presentation, histopathologic and immunohistochemical features, and treatment of a patient with primary ductal adenocarcinoma of the lacrimal gland. The current literature regarding this uncommon neoplasm also is reviewed.

RESULTS

Excisional biopsy revealed primary ductal adenocarcinoma of the lacrimal gland. The patient subsequently underwent extensive local resection of the tumor and is awaiting radiotherapy to the orbit and neck. A literature search revealed only 3 prior reports of primary ductal adenocarcinoma of the lacrimal gland.

CONCLUSIONS

Although uncommon, primary ductal adenocarcinoma of the lacrimal gland displays characteristic histologic and immunohistochemical findings that allow its distinction from the other primary lacrimal gland adenocarcinomas. Awareness and recognition of this rare malignancy may aid in further delineation of its biologic behavior, management, and prognosis.

Differential effect of retinoic acid and triiodothyronine on the age-related hypo-expression of neurogranin in rat

Given the important role of retinoids and thyroid hormone for optimal brain functioning and the tenuous relationship between retinoic acid (RA) and triiodothyronine (T3) signalings, we compared the effects of RA or T3 administrations on RA and T3 nuclear receptors (RAR, RXR and TR) and on their target genes, neuromodulin (GAP43) and neurogranin (RC3) in 24-month-old rats. Quantitative real time PCR and western blot analysis allowed us to verify that retinoid and thyroid signalings and GAP43 and RC3 expression are affected by age. By in situ hybridization we observed a decreased expression of RC3 in hippocampus, striatum and cerebral cortex. RARbeta, RXRbeta/gamma and GAP43 were up-regulated by RA as well as T3 treatment. The abundance of TRalpha/beta mRNA and RC3 expression were only increased by T3 administration in the whole brain. This up-regulator effect of T3 on RC3 was only observed in the striatum. During aging, T3 become a limiting factor alone able to correct the age-related concomitant hypo-activation of retinoid and thyroid signalings and alterations of synaptic plasticity.

[Hereditary neuralgic amyotrophy: a paediatric and familial presentation of Parsonage-Turner syndrome]

Hereditary neuralgic amyotrophy is a rare disorder, characterized by recurrent attacks of pain in a brachial plexus distribution. We report the case of a 12-year-old boy with several attacks of pain and atrophy of the muscles of the shoulders. The age of onset of this disease is variable, most frequently in the second or third decade. Pediatric onsets, during the first decade are rare. The differences between the hereditary neuralgic amyotrophy and the sporadic Parsonage-Turner syndrome are painful recurrent episodes of weakness and similar familial cases. The analysis of several families has shown that hereditary neuralgic amyotrophy phenotype is heterogeneous and two different clinical courses can be discerned. Recent evidence indicates that HNA is genetically heterogeneous. Pathophysiology of the disease remains unclear, so the treatment is not clearly established.

Expression of neurogranin and neuromodulin is affected in the striatum of vitamin A-deprived rats

Our previous data showed that vitamin A deficiency (VAD) induces, in whole brain, a reduced amount of mRNA for brain retinoic acid (RA) and triiodothyronine (T3) nuclear receptors (i.e., RAR, RXR, and TR, respectively), which is accompanied by reduced amounts of mRNA and protein of neurogranin (RC3, a neuronal protein involved in synaptic plasticity) as well as selective behavioral impairment. Given the important role of retinoids for optimal brain functioning, the effects of vitamin A depletion and subsequent administration of RA or T3 on the mRNA levels of RA and T3 nuclear receptors and on two target genes' (RC3 and neuromodulin or GAP43) mRNA and protein levels were examined in the hippocampus, striatum, and cerebral cortex. A quantitative real-time polymerase chain reaction (PCR), in situ hybridization, and Western blot analysis demonstrated that the striatal region is the brain site where both RA and T3 signaling pathways are most affected by VAD. Indeed, rats fed a vitamin A-free diet for 10 weeks exhibited decreased expression of RAR, RXR, TR, RC3, and GAP43 in the striatum. The administration of T3 to these vitamin A-deprived rats reversed the reduction in mRNA levels of RA and T3 nuclear receptors and in mRNA and protein levels of target genes in this region. These data suggest that modifications that appear preferentially in the striatum, a region highly sensitive to vitamin A bioavailability, may contribute to neurobiological alterations and the spatial learning impairment that occurs in vitamin A-deprived animals.

[Neurologic emergencies in the child]

Febrile seizures are the main causes of seizures in infants and children. They are caused by the fever without infectious of nervous central system. The diagnosis of acute encephalitis should be suspected in febrile children whose level of consciousness is progressively altered and who present with partial seizures and motor deficit. The two most classical etiologies of ataxias are cerebellar involvement or deep sensibility disorder. Acute drug poisoning and viral infections are the most common causes. Intracranial hypertension is due to an abnormal increase in cerebrospinal fluid pression. Acute form may be a life threatening or complication of chronic intracranial hypertension. Despite its high frequency, benign form should be remain a diagnosis of exclusion.

Orbital malignant fibrous histiocytoma following irradiation for retinoblastoma

PURPOSE

An unusual case is reported of orbital malignant fibrous histiocytoma that developed after irradiation for retinoblastoma.

METHODS

Case report.

RESULTS

A 5-month-old girl underwent enucleation of the left eye, external beam irradiation of the right eye, and systemic chemotherapy for bilateral sporadic retinoblastoma. At age 17 years, a malignant fibrous histiocytoma developed in the medial aspect of the orbit and nasal cavity. After attempted excisional biopsy, she underwent craniofacial resection, orbital exenteration, maxillectomy, and tracheostomy. The patient was alive 12 months postoperatively without local or metastatic disease.

CONCLUSIONS

Although orbital fibrous histiocytoma occurs usually as a primary tumor of adulthood, it can also develop as a secondary tumor after irradiation for retinoblastoma.

Epstein-Barr virus-associated adult respiratory distress syndrome in a patient with AIDS: a case report and review

BACKGROUND

Epstein-Barr virus (EBV) infection has been associated with fatal pneumonitis in immunocompetent patients. We present a case of fatal adult respiratory distress syndrome caused by EBV infection in a patient with acquired immunodeficiency syndrome (AIDS), to our knowledge the first such reported case, along with a survey of archival autopsy cases to assess baseline expression of EBV in AIDS patients.

DESIGN

The case patient's autopsy material was studied exhaustively for infectious agents by culture, histochemistry, and immunohistochemistry, with negative results. Formalin-fixed paraffin-embedded lung, spleen, lymph node, and liver tissue were further studied by in situ hybridization using a probe for EBV early RNA (EBER, Kreatech). The same method was applied to lymphoid tissues from eight other archival AIDS autopsy cases. Case patient tissues were also examined by electron microscopy.

RESULTS

Strikingly numerous lymphocytes were positive for EBV early RNA in the case patient's spleen, lymph nodes, and hepatic portal areas. In addition to positive lymphocytes in the lung, EBV-infected pneumocytes were also present. Electron microscopy also demonstrated viral material in lymphocytes and pneumocytes. Of the archival cases studied, only one spleen was found to have rare positive lymphocytes.

CONCLUSION

Primary or reactivation EBV infection may represent a previously underreported cause of morbidity and mortality in AIDS patients. Autopsy tissues from AIDS patients do not routinely show overexpression of EBV early RNA by in situ hybridization, making this technique ideal for assessing the contribution of EBV to terminal events in these patients.

Does the short variant of the serotonin transporter linked polymorphic region constitute a marker of alcohol dependence?

The serotonin (5-hydroxytryptamine: 5-HT) system has been thought to play an important role in several steps of alcohol craving. A number of studies, including our own, have reported that alcohol dependence is associated with dysfunction of 5-HT transmission. Pharmacological and clinical studies have shown that the 5-HT transporter (5-HTT) and the 5-HT1A receptor appear to be candidate loci for the aetiology of alcohol dependence. We have analysed the presence of different 5-HTT and 5-HT1A variants in 104 alcohol-dependent patients and 38 controls for a possible association with alcohol dependence. In alcohol-dependent patients, we found a high frequency of the S allele of 5-HTTLPR (45.5% vs. 29%, chi2 = 6.33, p = 0.0081). No other significant differences were observed between the two populations for other polymorphisms. These results provide, for the first time, preliminary evidence that alcohol abuse disorders are associated with a genetic variant for 5-HT transmission. It might be possible to use this detection of the "S" allele as a clinical tool for pathology diagnosis and to advise recovering alcoholics and it could represent an aid to the prevention of relapse. Therapeutic actions could be envisaged to use this genotyping to help select the best therapeutic strategy.

Solitary intraosseous infantile myofibroma of the orbital roof

BACKGROUND

There are several rare tumors that can cause proptosis in an infant, including infantile myofibroma.

METHODS

A 3-month-old infant developed a painless, bone-destructive superomedial orbital mass, raising concern for orbital malignant neoplasms. Computed tomography disclosed a bone-destructive mass of the sphenoid wing. On magnetic resonance imaging, the intraosseous mass was well-circumscribed, surrounded by cortical bone, and showed prominent enhancement.

RESULTS

Superomedial orbitotomy and biopsy revealed a lesion composed of spindled to stellate cells, without mitotic activity, set in a fibromyxoid stroma. Immunohistochemical stains were positive for vimentin and actin. Ultrastructurally, there were actinlike thin filaments, mitochondria, and rough endoplasmic reticulum confirming a myofibroblastic proliferation and supporting the diagnosis of congenital infantile myofibroma.

CONCLUSION

Infantile myofibroma is a benign tumor that occurs rarely in the ocular region but can cause prominent bone destruction, misleading the clinician to suspect a malignant neoplasm.

Serum lipoprotein(a) [Lp(a)] in alcoholic men: effect of withdrawal

This study examines the effect of alcohol withdrawal on lipoprotein(a) [Lp(a)] in 24 male, middle-aged chronic alcohol abusers admitted for withdrawal therapy. Serum concentration of Lp(a) was determined before and during the first 3 weeks of abstinence. The changes in three sialylated proteins [Lp(a), alpha 1-antitrypsin (alpha 1-AT), and haptoglobin (Hp)] and in desialylated transferrin (CDT) were also determined in 14 patients. After the 3 weeks of withdrawal therapy, the mean and median Lp(a) concentrations increased (p = 0.0001). The changes in Lp(a) levels were not related to the changes in dietary intake nor to the decrease in total HDL, HDL3, HDL2 cholesterol, Apo A-I, and Apo B. In the subgroup of 14 chronic alcohol abusers, Lp(a) levels increased parallel with Hp and alpha 1-AT, whereas CDT decreased. It is concluded that the impact of alcohol on sialylated proteins may be one of the mechanisms responsible for the increase in plasma Lp(a) after alcohol withdrawal.

Adenoid cystic carcinoma of Bartholin's gland: a review of the literature and report of a patient

We report the case of a 77-year-old white female with adenoid cystic carcinoma of Bartholin's gland. To date only 45 cases of adenoid cystic carcinoma of Bartholin's gland have been reported in the world literature. The longest reported survival is 27 years. This patient was originally diagnosed 33 years ago and presented with her fourth recurrence. She was treated with radical surgery and did well for 6 months, but later died secondary to renal failure. Adenoid cystic carcinoma of the Bartholin's gland is a rare tumor of the vulva. When diagnosed the treatment should be tailored to the patient. When margins are found to be positive, adjuvant radiotherapy may prove to be beneficial.

Primitive neuroectodermal tumor of the orbit

A 10-year-old girl developed a lump in the lateral aspect of the right eyebrow over a 3-week period. Computed tomography and magnetic resonance imaging revealed a soft-tissue mass in the superolateral aspect of the right orbit associated with zygo-maticofrontal bone erosion and hyperostosis. An incisional biopsy specimen was studied using light microscopy, immunohistochemical staining, and electron microscopy, resulting in a diagnosis of peripheral primitive neuroectodermal tumor. The results of an extensive evaluation for systemic involvement were negative. The patient was subsequently treated with chemotherapy and radiation therapy. Primary primitive neuroectodermal tumor of the orbit is rare. The differential diagnosis and the diagnostic features of this entity are discussed herein.

Ex vivo pharmacodynamic study of piperacillin alone and in combination with tazobactam, compared with ticarcillin plus clavulanic acid

Ten volunteers received piperacillin (4 g), piperacillin (4 g) plus tazobactam (0.5 g) (Tazocin), and ticarcillin (3 g) plus clavulanic acid (0.2 g) (Timentin) intravenously over 30 min in a cross-over blinded scheme. Blood samples were obtained 0.5 and 3 h after the end of infusion to measure by (high-pressure liquid chromatography) the concentration and bactericidal titers against 70 gram-negative bacilli. Serum time-kill curves were done against 35 strains to measure killing rates and area under the time-kill curve. Using the measure of serum bactericidal activity, ticarcillin-clavulanic acid and piperacillin-tazobactam were equally effective against Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloacae, Serratia marcescens, and Bacteroides fragilis. Piperacillin-tazobactam was superior to ticarcillin-clavulanic acid against piperacillin-resistant Klebsiella pneumoniae (4 to 16 times) and S. marcescens (2 to 4 times). By using the area under the time-kill curve, piperacillin-tazobactam was equivalent to ticarcillin-clavulanic acid against piperacillin-susceptible strains; piperacillin-tazobactam was significantly more active than piperacillin against piperacillin-resistant strains and was more active than ticarcillin-clavulanic acid when the sample obtained 3 h after the end of infusion to volunteers was considered. Serum piperacillin concentrations (mean +/- standard error of the mean; in mg/liter) were 115 +/- 13 at 0.5 h and 7.4 +/- 1.4 at 3 h after the administration of piperacillin alone and 105.5 +/- 12.6 (0.5 h) and 7.7 +/- 1.6 after the administration of piperacillin-tazobactam. Serum tazobactam concentrations (in milligram per liter) were 13.1 +/- 1.4 at 0.5 h and 1.2 +/- 0.2 at 3 h. The piperacillin-tazobactam ratio was 8 +/- 0.3 at 0.5 h and 6.2 +/- 0.5 at 3 h. Piperacillin-tazobactam appears promising against beta-lactamase-producing gram-negative bacilli.

Influence of teicoplanin and vancomycin on degranulation by polymorphonuclear leucocytes stimulated by various agonists: an in-vitro study

The interaction between vancomycin and teicoplanin (50 and 100 mg/l) on human neutrophils was studied using fMLP- and A23187-induced degranulation of elastase, beta-glucuronidase and vitamin B12-binding-protein. Each of these proteins is a marker of a different population of granules. fMLP-induced degranulation of beta-glucuronidase was significantly impaired by pre-incubating the neutrophils with teicoplanin (without affecting cell viability) although the inhibition was at most 23% at 100 mg/l, a concentration not achieved in the serum of patients after normal doses. Calcium ionophore-induced degranulation of beta-glucuronidase and elastase were slightly impaired (Student two-tailed; P less than 0.1) by both glycopeptides (beta-glucuronidase) and teicoplanin only (elastase). Again, inhibition remained below 25%. Vancomycin and teicoplanin at high concentrations, seldom achieved in patients, can moderately impair neutrophil degranulation.

Influence of rifampicin and ansamycin on motility and adherence of human neutrophils studied in vitro

We have studied the influence of rifampicin and ansamycin on chemotaxis, random migration and adherence to plastic of human neutrophils. Neutrophils were preincubated for 30 min at 37 degrees C with the antibiotics. Chemotaxis was studied in antibiotic-free and antibiotic-containing agar using zymosan-activated serum and fMLP as stimuli. Adherence was studied in plastic microtitre plates. Rifampicin and LM427 (ansamycin, 6 mg/l) did not impair differential migration, but inhibited random migration. At clinically achievable concentration (greater than or equal to 6 mg/l), inhibition was less than or equal to 18%. The chemokinetic response curve induced by different concentrations of fMLP was not modified by the two antibiotics. Adherence to polystyrene was significantly increased and could explain the inhibition of random migration.

Penetration of ciprofloxacin in bronchial secretions after intravenous administration

Ciprofloxacin concentrations in serum and in bronchial secretions were studied after single and multiple intravenous administrations for two days in ten patients. The dose given was either 0.75 or 1.5 mg/kg. With the lower dose, the peak concentrations in the bronchial secretions were (mean +/- S.D.) 0.40 +/- 0.29 mg/l after the first injection and 0.35 +/- 0.25 mg/l after the fourth injection. With the higher dose, the corresponding mean peak bronchial concentrations were 0.84 +/- 0.58 and 1.16 +/- 0.86 mg/l respectively. The half-lives of the drug in bronchial secretions ranged from 2.13 to 3.72 h. The penetration of ciprofloxacin into bronchial secretions was excellent as demonstrated by the high ratios of the areas under the concentration curves obtained in the serum and in bronchial secretions which ranged from 0.79 to 1.11.

Effect of NaCl and urea concentration comparable to renal medulla on superoxide production by human polymorphonuclear leukocytes

The influence of hyperosmolarity on superoxide production by polymorphonuclear leukocytes (PMNL) was examined using NaCl and urea as osmotic substances. Superoxide production was inhibited in a hyperosmotic environment produced by high concentrations of these substances with the following IC50: 440 +/- 75 (SD) mOsm/kg for NaCl and 660 +/- 100 for urea. In the case of NaCl, this inhibition was time-dependent and abolished at 4 degrees C. Since PMNL pump out Na+ ion for maintenance of cellular volume in an energy dependent fashion, it was suggested that the inhibition of superoxide production was due to the exhaustion of energy stores. On the other hand, urea inhibition was almost immediate and remained even when preincubation was performed at 4 degrees C. Because the transport of urea through the cell membrane is known to be energy independent, these findings suggested that urea was either an inhibitor of the NADPH oxidase or a scavenger of superoxide anion.

Intraphagocytic penetration of antibiotics

The penetration of several antibiotics into human polymorphonuclear leucocytes was measured with a bioassay. The aminoglycosides (gentamicin, netilmicin), oxacillin and LY146032, a new lipopeptidic antibiotic, had a penetration which was generally less than 60%, whereas new fluoro-quinolones (enoxacin, ciprofloxacin, CI934, Ro236240) and rifamycins (rifampicin, LM427) were concentrated 2.4 to 14.2-fold. The concentration of vancomycin and teicoplanin associated with the neutrophils appeared to be saturable over the range of extracellular concentrations tested (5-20 mg/l). Coumermycin, an inhibitor of DNA-gyrase, was highly concentrated (11.3 to 16.6-fold) within the neutrophils. The penetration of clindamycin and erythromycin was low (0.60- to 1.48-fold).

Bactericidal activity and killing rate of serum in volunteers receiving pefloxacin alone or in combination with ceftazidime, piperacillin or mezlocillin against Pseudomonas aeruginosa

The activity of the combination of pefloxacin with ceftazidime, piperacillin, or mezlocillin was compared to the activity of the same antibiotics given alone, by measurement of serum bactericidal titres and the rate of killing of ten strains of Pseudomonas aeruginosa. Three groups of five volunteers each received pefloxacin (12 mg/kg iv) with or without ceftazidime, piperacillin or mezlocillin (25 mg/kg iv). Serum samples were obtained at the end of the infusion. The mean serum concentration of pefloxacin at this time was 13.9 mg/l (3.2, S.D.). The activity of each of the three combinations was identical to the corresponding activity of the beta-lactam alone. However, the emergence of resistance to pefloxacin was prevented by ceftazidime (five out of five strains), and piperacillin (two out of five strains). We conclude that combinations of pefloxacin with beta-lactam antibiotics may not increase efficacy against P. aeruginosa.

Influence of LY146032 on human polymorphonuclear leucocytes in vitro

LY 146032 is a new acidic lipopeptide antibiotic with high in-vitro activity against Gram-positive bacteria. We have studied the influence of LY 146032 on the functions of polymorphonuclear leucocytes with two strains of Staphylococcus aureus, one susceptible to oxacillin and one resistant. LY 146032 (10 mg/l) was found to have no influence on superoxide generation stimulated by phorbol myristate acetate, nor on phagocytosis of opsonized Staph. aureus, furthermore there was no effect on chemotaxis in agar stimulated by opsonized zymosan. LY 146032 (MIC and MIC/4) did not modify the intracellular killing of the two strains when they were preincubated, or when the antibiotic was added either at the time or after the completion of phagocytosis both in aerobic and in strict anaerobic conditions. However, in aerobic conditions, LY 146032 was able to prevent the overgrowth of phagocytosed Staph. aureus after 24 h of incubation. The intracellular concentration of LY 146032, measured by microbiological assay, was 60% of the extracellular concentration.

Influence of various antibiotics on phagocytosis of Staphylococcus aureus by human polymorphonuclear leucocytes

The influence of several new antibiotics on phagocytosis of two strains of Staphylococcus aureus by human polymorphonuclear leucocytes was studied with a radioisotopic method. The following antibiotics were tested in concentrations obtained in the serum after standard administration: gentamicin, netilmicin, amikacin, oxacillin, clindamycin, vancomycin, teicoplanin, rifampicin, ansamycin, coumermycin, enoxacin, ciprofloxacin, two new fluoro-quinolones CI 934 and RO 236240, and LY 146032 a new lipopeptidic antibiotic. Among them, only coumermycin significantly decreased phagocytosis, this was dependent on concentration, strain and source of the polymorphonuclear leucocytes.

In-vitro activity of two new carbapenems FCE 22101 and CGP 31608 in comparison with imipenem

The minimum inhibitory concentrations (MICs) of two new penems, CGP 31608 and FCE 22101 were evaluated against 993 aerobic Gram-positive and Gram-negative bacteria and compared with imipenem. FCE 22101 was usually two to eight-fold more active than CGP 31608 except for Pseudomonas aeruginosa against which FCE 22101 was inactive. Both new penems were less active than imipenem. MBCs were equal to 1-2 X MICs. The effects of inocula, cations and serum were minimal. The MICs and MBCs were higher at pH 8 than at pH 6 or 7. Synergy between the new penems and amikacin was detected in 30% of the strains studied. Antagonism occurred with some Gram-positive bacteria.

Comparative serum bactericidal activity against test anaerobes in volunteers receiving imipenem, clindamycin, latamoxef and metronidazole

Ten healthy volunteers received on separate days the following regimens: imipenem 500 mg, clindamycin 600 mg, latamoxef 1 g, and metronidazole 500 mg. The antibiotics were given intravenously as an infusion over 15 min. Blood samples were obtained before and 30 min, 1 and 6 h after the start of the infusion. Serum bacteriostatic and bactericidal activities were measured against the following strains of strict anaerobes: two strains of Bacteroides fragilis, one strain each of B. vulgatus, B. thetaiotaomicron, B. oralis, Fusobacterium symbiosum, Eubacterium lentum, Clostridium perfringens, and Peptostreptococcus magnus. Sera from patients receiving clindamycin showed the highest inhibitory and bactericidal activities except against B. thetaiotaomicron and F. symbiosum. Imipenem had similar inhibitory and bactericidal activity to that shown by latamoxef. Metronidazole had a moderate activity against all strains although the activity persisted for 6 h. Latamoxef was the most active antibiotic against the test strain of C. perfringens.

Influence of various antibiotics on superoxide generation by normal human neutrophils

Among the several killing mechanisms displayed by human neutrophils, the oxidative system is the most efficient. We have studied the influence of various antibiotics on the generation of superoxide by isolated human polymorphonuclear leukocytes (PMNL) stimulated by phorbol-myristate acetate. Among the antibiotics tested, only coumermycin significantly inhibited superoxide generation; this effect was dose-related, it depended on extracellular calcium concentration and was potentiated by sub-inhibitory concentrations of calcium channel-blocking agents. Coumermycin inhibited the influx of calcium produced by the ionophore A23187 as well as directed chemotaxis in agar and the intracellular killing of a highly susceptible strain of S. aureus. These inhibitory effects required at least 15 min of preincubation of the PMNL. Coumermycin, at clinically achievable serum concentrations, significantly impaired several PMNL functions. The mechanism could be a specific or a non-specific interaction with calcium-channels.

Serum bactericidal activity and killing rate for volunteers receiving imipenem, imipenem plus amikacin, and ceftazidime plus amikacin against Pseudomonas aeruginosa

Serum bactericidal activity against 20 strains of Pseudomonas aeruginosa was studied in 10 volunteers after administration of imipenem (25 mg/kg), imipenem (25 mg/kg) plus amikacin (7.5 mg/kg), and ceftazidime (25 mg/kg) plus amikacin (7.5 mg/kg). Eight strains were susceptible and 12 were resistant to ticarcillin. Serum levels were measured microbiologically after 30 and 60 min and were, respectively, 97 and 46 micrograms/ml for imipenem given alone and 79 and 45 micrograms/ml for imipenem given with amikacin. Despite the very large dose of imipenem used, imipenem and imipenem plus amikacin appeared slightly less active than ceftazidime plus amikacin (P less than or equal to 0.1; Wilcoxon matched-pairs test), with respective median titers at 30 min of 1:128, 1:128, and 1:256 against ticarcillin-susceptible strains and 1:32, 1:32, and 1:64 against ticarcillin-resistant strains; however, more than 90% of the serum determinations, regardless of the regimen, had a serum bactericidal activity greater than or equal to 1:8. Amikacin significantly increased the rate of killing in serum of P. aeruginosa by imipenem. Imipenem plus amikacin appeared as effective as ceftazidime plus amikacin in reducing the viable counts of P. aeruginosa after 24 h of incubation.

Bactericidal activity and killing rate of serum from volunteers receiving pefloxacin alone or in combination with amikacin

Serum bactericidal activities (SBAs) were studied after intravenous administration of pefloxacin (8 mg/kg) and amikacin (7.5 mg/kg) alone or in combination to 15 human volunteers. About 10 strains each of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus were tested. The serum levels of pefloxacin were measured microbiologically by using E. coli KP 1976-712 as the test organism at 0, 30, 60, 120, and 720 min after infusion; at 0, 30, 60, and 720 min these levels were 7 +/- 1.4, 5 +/- 0.8, 4.5 +/- 0.7, and 2.1 +/- 0.6 mg/liter (mean +/- standard deviation), respectively, with a terminal half-life of 10 h. The serum levels of pefloxacin in the presence of amikacin were measured similarly; 1% sodium polyanethol sulfonate was added to the agar to inactivate amikacin. Treatment with pefloxacin alone resulted in high SBAs against E. coli, K. pneumoniae strains susceptible to cephalothin, and Staphylococcus aureus at the peak concentration; 81 to 100% of the sera had SBAs of greater than or equal to 1:8. However, treatment with pefloxacin alone resulted in low SBAs against K. pneumoniae strains resistant to cephalothin and P. aeruginosa; only 34% of the sera had SBAs of greater than or equal to 1:8. At trough concentrations the percentages of sera with SBAs greater than or equal to 1:8 were 75 to 83% (E. coli), 9 to 27% (K. pneumoniae), 0% (P. aeruginosa), and 10% (S. aureus). The combination of pefloxacin plus amikacin was most often additive; the peak activity was due to amikacin, and the trough activity was due to pefloxacin. Occasionally antagonism occurred with P. aeruginosa, K. pneumoniae, and S. aureus strains. These observations were confirmed by the killing curves in pooled serum obtained at peak and trough levels. Regrowth was observed for seven strains of P. aeruginosa treated with pefloxacin alone; amikacin seemed to prevent this phenomenon.

Bactericidal activity of ciprofloxacin in serum and urine against Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus and Streptococcus faecalis

Ten volunteers received three doses of 500 mg ciprofloxacin, orally every 12 hours. After the last dose, mean serum levels were (mg/l +/- SD) 2.4 +/- 0.83 at 1 h; 0.91 +/- 0.30 at 4 h and 0.18 +/- 0.04 at 12 h. At 1 h the median serum bactericidal activity was satisfactory only against the Escherichia coli (1:256) and Klebsiella pneumoniae (1:128). In urine collected from 0 to 4 h and 8 to 12 h after the last dose, the mean ciprofloxacin level was respectively 482.5 +/- 324.7 and 80.9 +/- 48.2 mg/l +/- SD. Bactericidal activity in urine was high even against the least susceptible species tested: Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus faecalis. A post antibiotic effect was demonstrated in 22 out of the 29 strains tested, ranging mainly from 1 to 3 h. Ciprofloxacin 500 mg orally twice a day is a bactericidal regimen against a wide range of urinary pathogens but has a limited systemic activity.

Comparative in-vitro activities of azlocillin, ticarcillin and ticarcillin plus clavulanic acid against Staphylococcus aureus, Klebsiella pneumoniae and Pseudomonas aeruginosa

Azlocillin (5 g), ticarcillin (5 g) and ticarcillin (5 g) plus clavulanic acid (200 mg) were administered intravenously on separate days to human volunteers. Serum levels 1 h after the infusion were (mean +/- S.E.): 263 +/- 40 mg/1 for azlocillin, 238 +/- 56 mg/l for ticarcillin and 5.5 +/- 1.9 mg/l for clavulanic acid. Serum withdrawn at 0.5 h was titrated against ten strains of Staphylococcus aureus, ten Klebsiella pneumoniae and nine Pseudomonas aeruginosa of which four were resistant to ticarcillin. Against Staph. aureus and K. pneumoniae, median serum bactericidal activity (SBA) and percentage of sera with SBA greater than or equal to 1:8 were greater with ticarcillin plus clavulanic acid (median SBA 1:32 and 85% of sera with SBA greater than or equal to 1:8) than with the other two regimens. There were no differences in activity against Ps. aeruginosa.

Inactivation of netilmicin and amikacin by intact or disrupted leucocytes

The bio-inactivation of netilmicin and amikacin by binding with intact and disrupted human normal leucocytes was compared. Even after prolonged incubation of the aminoglycosides with intact cells, no binding could be demonstrated. On the other hand, partial binding of netilmicin and amikacin by disrupted leucocytes occurred: a linear relationship between the logarithm of the initial number of cells and the degree of binding of the drug was observed. The decrease in biological activity occurred rapidly in the presence of disrupted cells and remained unchanged during the next 18 h.

Serum bactericidal activity of aztreonam, cefoperazone, and amikacin, alone or in combination, against Escherichia coli, Klebsiella pneumoniae, Serratia marcescens, and Pseudomonas aeruginosa

Serum samples from volunteers receiving (per kilogram) 20 mg of aztreonam, 20 mg of cefoperazone, 7.5 mg of amikacin, 20 mg of cefoperazone plus 20 mg of aztreonam, or 20 mg of aztreonam plus 7.5 mg of amikacin were evaluated for bactericidal activity against Escherichia coli, Klebsiella pneumonia, Serratia marcescens, and Pseudomonas aeruginosa. Serum bactericidal activities were similar for aztreonam alone or in combination but were lower for amikacin and cefoperazone alone, especially against S. marcescens and P. aeruginosa. Killing studies, performed with serum samples diluted 1:8, demonstrated a high killing rate for aztreonam plus amikacin, especially against P. aeruginosa.

Serum bactericidal activity of cefoperazone and ceftazidime at increasing dosages against Pseudomonas aeruginosa

Serum bactericidal activity (SBA) greater than or equal to 1:8 correlates with the clinical effectiveness of antibiotics. Ten healthy young volunteers received iv on separate days cefoperazone 1, 2, or 3 g and ceftazidime 1, 2, or 3 g. The serum levels 1 and 6 h after the administration of cefoperazone 1, 2 and 3 g were respectively 52 and 7 mg/l, 122 and 13 mg/l, 190 and 22 mg/l. The serum levels of ceftazidime 1, 2 and 3 g, after 1 h and 6 h were 28 and 8, 56 and 9, 78 and 13 mg/l. The SBA was determined against seven strains of Pseudomonas aeruginosa with MBC of 1.6-12.5 mg/l of cefoperazone and 0.8-6.2 mg/l of ceftazidime. Increased dosage of cefoperazone and ceftazidime led to a significant increase in the SBA's greater than or equal to 1:8 at 1 h (P less than 0.01). In sera obtained 1 h and 6 h after the injection of the antibiotics, 97% and 51% of the strains were inhibited by ceftazidime 2 g, while 1 g was inhibitory on 84% (1 h) and 8% (6 h) of the strains. Ceftazidime 1 g produced SBA's greater than or equal to 1:8 significantly more often than did cefoperazone 3 g (P less than 0.01) at 1 h. The rate of killing with all ceftazidime regimens was similar and slightly higher than that of any cefoperazone regimen. Ceftazidime seems more effective than cefoperazone against Ps. aeruginosa; however, increased MBC values were observed during killing curves studies with both drugs.