Penicillin neurotoxicity

A case report of treatment of a streptococcal brain abscess with ceftobiprole supported by the measurement of drug levels in the cerebrospinal fluid

In this paper, we describe the case of a patient admitted to our hospital because of a brain abscess due to Streptococcus intermedius. The management of brain abscess is challenging given the limited potential drug options with effective penetration into both the central nervous system and the abscess capsule to achieve adequate therapeutic concentrations. Due to the high anti-streptococcal activity of ceftobiprole and the availability of ceftobiprole therapeutic drug monitoring in our hospital, we decided to treat the patient with ceftobiprole. To maximize the antimicrobial effect of ceftobiprole, we chose a prolonged intravenous infusion, and we monitored its concentrations in both plasma and cerebrospinal fluid.

Neurological Adverse Effects Attributable to β-Lactam Antibiotics: A Literature Review

β-lactam antibiotics are commonly prescribed antibiotic drugs. To describe the clinical characteristics, risk markers and outcomes of β-lactam antibiotic-induced neurological adverse effects, we performed a general literature review to provide updated clinical data about the most used β-lactam antibiotics. For selected drugs in each class available in France (ticarcillin, piperacillin, temocillin, ceftazidime, cefepime, cefpirome, ceftaroline, ceftobiprole, ceftolozane, ertapenem and aztreonam), a systematic literature review was performed up to April 2016 via an electronic search on PubMed. Articles that reported original data, written in French, Spanish, Portuguese or English, with available individual data for patients with neurological symptoms (such as seizure, disturbed vigilance, confusional state, myoclonia, localising signs, and/or hallucinations) after the introduction of a β-lactam antibiotic were included. The neurological adverse effects of piperacillin and ertapenem are often described as seizures and hallucinations (>50 and 25% of cases, respectively). Antibiotic treatment is often adapted to renal function (>70%), and underlying brain abnormalities are seen in one in four to one in three cases. By contrast, the neurological adverse drug reactions of ceftazidime and cefepime often include abnormal movements but few hallucinations and seizures. These reactions are associated with renal insufficiency (>80%) and doses are rarely adapted to renal function. Otherwise, it appears that monobactams do not have serious neurological adverse drug reactions and that valproic acid and carbapenem combinations should be avoided. The onset of disturbed vigilance, myoclonus, and/or seizure in a patient taking β-lactam antibiotics, especially if associated with renal insufficiency or underlying brain abnormalities, should lead physicians to suspect adverse drug reactions and to consider changes in antibacterial therapy.

A Case Attributed to Cefazolin and a Review of the Literature

Generalized convulsions developed in a uremic patient who had received massive doses of cefazolin which resulted in a measured serum level of greater than 512 mcg/ml of drug after dialysis. Pathophysiologic mechanisms which could have contributed to the symptoms are discussed. Physicians prescribing cefazolin and other cephalosporins need to be aware of this potential complication of therapy and adjust doses accordingly in renal failure.

Antibiotic-induced neurotoxicity

Antibiotic neurotoxicity is rare but can cause significant morbidity when it occurs. The risk of antibiotic neurotoxicity appears to be highest in patients who are older, have impaired renal function, or have preexisting neurologic conditions. This review describes the clinical features of the most common antibiotic toxicities affecting the nervous system: seizures, encephalopathy, optic neuropathy, peripheral neuropathy, and exacerbation of myasthenia gravis.

Drug-induced myoclonus: frequency, mechanisms and management

Myoclonus is a sudden, abrupt, brief, 'shock-like' involuntary movement caused by muscular contractions ('positive myoclonus') or a sudden brief lapse of muscle contraction in active postural muscles ('negative myoclonus' or 'asterixis'). Various disorders can cause myoclonus including neurodegenerative and systemic metabolic disorders and CNS infections. In addition, myoclonus has been described as an adverse effect of some drugs. Level II evidence is available to indicate that levodopa, cyclic antidepressants and bismuth salts can cause myoclonus, while there is less robust evidence to associate numerous other drugs with the induction of myoclonus. The pharmacological mechanisms responsible for this adverse effect are not well established, although increased serotonergic transmission may be involved in the induction of myoclonus by several drugs. Drug-induced myoclonus usually resolves after withdrawal of the offending drug, but in some cases specific treatments are needed.

Antibiotic side effects

Antibiotic side effects are approached best from an individual agent perspective rather than from a class-related standpoint. As this article indicates, with the exception of drug fevers and drug rashes, most antibiotic side effects are related to individual agents and not class side effects. Clinicians should view antimicrobial side effects as related to each organ system and be aware that more often a nonmicrobial medication is the explanation for the drug side effect rather than the antimicrobial. Nonantimicrobial medications are the most common cause of drug fever; among antimicrobials, beta-lactams and sulfonamides are the most common causes of drug-induced fevers. Antimicrobial side effects have important implications for the patient, legal and economic implications for the hospital, and medicolegal implications for the physician. Antibiotic side effects that prolong hospitalization in today's managed care environment have important economic implications. Clinicians should be familiar with the most common side effects of the most frequently used antimicrobials, to minimize the potential of having adverse reactions occur in patients. Most adverse events related to antimicrobials are reversible rapidly on cessation of the medication. Irreversible toxicities include aminoglycoside-induced ototoxicity, Stevens-Johnson syndrome, and toxicity secondary to nitrofurantoin. The most common acute fatal drug reactions include hypersensitivity reactions resulting in anaphylaxis or the Stevens-Johnson syndrome and fatal hepatic necrosis secondary to trovafloxacin. Clinicians should eliminate the use of drugs associated with chronic or fatal toxicities because multiple therapeutic alternatives exist for virtually every potential infection.

[Central nervous system side effects of different antibacterial substances]

This review concerns central nervous system side effects of different antibacterial agents. Special attention is focussed on the new quinolone derivatives, penicillins and cephalosporins. As far as possible, mechanisms of action are discussed as well as therapeutic regimens.

Clinical features, pathogenesis and management of drug-induced seizures

Many classes of pharmacological agents have been implicated in cases of drug-induced seizures. The list includes antidepressant drugs, lithium salts, neuroleptics, antihistamines (H1-receptor antagonists), anticonvulsants, central nervous system stimulants, general and local anaesthetics, antiarrhythmic drugs, narcotic and non-narcotic analgesics, non-steroidal anti-inflammatory drugs, antimicrobial agents, antifungal agents, antimalarial drugs, antineoplastic drugs, immunosuppressive drugs, radiological contrast agents and vaccines. For each of these classes of drugs, this article offers a revision of the literature and emphasises in particular the frequency of the adverse reaction, its clinical presentation, its presumed epileptogenic mechanism and the therapeutic strategy for the management of drug-induced seizures. An attempt is also made to distinguish seizures induced by standard dosages from those provoked by accidental or self-induced intoxication. For some classes of drugs such as antidepressants, neuroleptics, central nervous system stimulants (e.g. theophylline, cocaine, amphetamines) and beta-lactam antibiotics, seizures are a well recognised adverse reaction, and a large body of literature has been published discussing exhaustively the major aspects of the issue; sufficient data are available also for the other classes of pharmacological agents mentioned above. In contrast, several other drugs [e.g. allopurinol, digoxin, cimetidine, protirelin (thyrotrophin releasing hormone), bromocriptine, domperidone, insulin, fenformin, penicillamine, probenecid, verapamil, methyldopa] have not been studied thoroughly under this aspect, and the only source of information is the occasional case report. This review does not address the issue of seizures induced by drug withdrawal.

Neurotoxicity of beta-lactam antibiotics. Experimental kinetic and neurophysiological studies

The neurotoxic potential of intravenous administered benzylpenicillin (BPC) was studied in rabbits with intact blood-CNS barriers and rabbits with experimental E. coli meningitis. At onset of epileptogenic EEG activity or seizures, serum, CSF and brain tissue were collected for assay of BPC. Based on the fact that, in tissues, BPC seems to remain extracellularly, brain concentrations of BPC were expressed as brain tissue fluid (BTF) levels, calculated as 10x the concentration in whole brain tissue. Neurotoxicity could be precipitated in all rabbits. In normal rabbits BTF levels of BPC were considerably higher than those in CSF indicating a better penetration across the blood-brain barrier (BBB). BPC penetrated better to CSF and BTF in meningitic rabbits than in normal controls, suggesting some degree of damage of the BBB concomitant with meningeal inflammation. E. coli meningitis did not increase the neurotoxicity of BPC. In control rabbits the intracisternal injection of saline resulted in some degree of pleocytosis. Unmanipulated animals are therefore preferable as controls. Epileptogenic EEG-changes was the most precise of the two variables used for demonstration of neurotoxicity. EEG-changes were therefore used as neurotoxicity criterion in the following rabbit experiments. To evaluate the effect of uraemia alone and uraemia plus meningitis on the neurotoxity of BPC in rabbits, cephaloridine was used to induce uraemia. Meningitis was induced by intracisternal inoculation of a cephalosporin resistant strain of E. cloacae. Untreated rabbits were used as controls. Uraemia resulted in increased BTF penetration of BPC, possibly explained by permeability changes in the BBB and/or decreased binding of BPC to albumin. Uraemia did not result in increased penetration of BPC into the CSF of non-meningitic rabbits. Uraemic non-meningitic rabbits had the highest BTF levels of BPC at the criterion, indicating that cephaloridine-induced renal failure increased the epileptogenic threshold in these rabbits. The combination of uraemia and meningitis increased the neurotoxicity of BPC since the criterion was reached at considerably lower BTF levels of BPC. Meningitis, either alone or together with uraemia, did not increase the neurotoxicity in comparison to control rabbits. Higher BTF levels of BPC were found in meningitic rabbits than in controls with intact blood-CNS barriers at onset of EEG-changes. In all groups of rabbits there was a pronounced variability of BPC levels in the CSF while the intra-group variations in BTF levels were much smaller. Thus, BTF and not CSF levels were decisive for the neurotoxicity of BPC.(ABSTRACT TRUNCATED AT 400 WORDS)

The effect of probenecid on the renal tubular excretion of benzylpenicillin

1 The aim of this study was to establish whether the renal tubular excretion of benzylpenicillin is saturable and whether the effect of probenecid on the tubular excretion of benzylpenicillin is dose-dependent. 2 Each of four volunteers underwent three experiments. In each experiment benzylpenicillin was administered by continuous infusion, such that three different consecutive concentration levels were reached. In the first experiment no probenecid was given; in the second and third experiments, probenecid was administered by continuous infusion at a low and higher rate, respectively. 3 Plasma and urinary concentrations of benzylpenicillin were determined at 30 min intervals by high performance liquid chromatography. 4 By fitting the equation Rtub = Rtub,max.Cp/(EC50 + Cp) to the values of the tubular excretion rate found for benzylpenicillin (Rtub) vs the free plasma concentration (Cp), the values of Rtub,max and EC50 could be calculated: 3350 (+/- 606) mg h-1 for Rtub,max and 48.0 (+/- 17.8) mg l-1 for EC50 (in the absence of probenecid). 5 The EC50 for benzylpenicillin increased significantly with increasing doses of probenecid. 6 The dose of probenecid at which 50% of the excretory system is occupied by probenecid in the absence of benzylpenicillin (ED50) ranged from 13.2 to 108.5 mg h-1. 7 The EC50 of probenecid in one subject could actually be measured: 52.3 mg l-1. 8 Extrapolating these results to the clinical situation, the commonly used daily dose of 2 g of probenecid is likely to be close to the maximal effective dose for inhibition of the tubular excretion of benzylpenicillin.

Effect of osmotic blood-brain barrier disruption on gentamicin penetration into the cerebrospinal fluid and brains of normal rabbits

Rapid infusion of hyperosmolar solutions into the internal carotid artery transiently disrupts the blood-brain barrier, permitting entry of substances that are ordinarily excluded from the nervous system. This study compared gentamicin concentrations in the cerebrospinal fluid (CSF) and brain tissue of rabbits receiving intracarotid infusions of 2 molal mannitol with those in three groups of control animals. After catheter placement and intravenous gentamicin administration (20 mg/kg), rabbits received either 2 molal mannitol in the internal carotid artery, 2 molal mannitol intravenously, 0.9% saline in the internal carotid artery, or 0.9% saline intravenously. Mannitol and saline were administered in 8-ml bolus injections over 40 s. After 2 h, serum, CSF, and brain specimens were obtained for antibiotic assay. Gentamicin concentrations in serum were comparable in all groups (mean concentrations ranged from 14.6 to 17.9 micrograms/ml at 60 min and from 5.7 to 7.4 micrograms/ml at 135 min), but gentamicin concentrations in CSF and brains were significantly higher in animals in the group receiving mannitol in the internal carotid artery. In this group the mean gentamicin concentration in CSF, 5.3 micrograms/ml, was twofold greater than those in the other three groups (range, 1.7 to 2.6 micrograms/ml). Similarly, the mean gentamicin concentration in the brains of animals in the group receiving mannitol in the internal carotid artery, 2.3 micrograms/g was significantly higher than those in the other groups (mean of measurable values, 1.4 micrograms/g, in all three control groups). Osmotic disruption of the blood-brain barrier enhanced the penetration of gentamicin into CSF and brain tissue.

Penicillin-induced coagulation disorder

A coagulation disorder was seen after penicillin-G administration (10 million units/day) in uraemic patients and after high-dose penicillin G (40 million units/day) in patients with a normal glomerular filtration-rate (5 patients after cardiac surgery). This disorder was characterised by: prolongation of bleeding-time, appearing immediately after penicillin-G administration and persisting until 4 days after withdrawal of therapy; disturbance of collagen-induced and ristocetin-induced platelet aggregation; increase of antithrombin-III activity; and inhibition of factor-xa activity. The inhibition of factor-xa activity corresponded to that seen after low-dose-heparin prophylaxis. The clinically latent coagulation disorder, when super-imposed upon pre-existing coagulation abnormalities (uraemia, treatment with anti-coagulants) may cause severe bleeding, as observed in 1 patient with acute renal failure on haemodialysis.

Intrathecal antibiotic therapy for neonatal meningitis

Twenty infants with neonatal meningitis were treated with systemic and lumbar intrathecal antibiotics upon initial diagnosis. Failure to sterilize the CSF in 2-3 days was associated with evidence of ventriculitis in these infants who were then treated with intraventricular antibiotics. 4 infants died, but only 2 of them may be regarded as treatment failure. It is suggested that many deaths from neonatal meningitis may be preventable by early detection and treatment of ventriculitis with intraventricular antibiotics.

Antibiotic neurotoxicity. Laboratory and clinical study

✓ By ventriculocisternal perfusion, a series of newer antibiotics were circulated through the central nervous system to ascertain the potential toxicity of these drugs to the nervous parenchyma. Ampicillin, carbenicillin, gentamycin sulfate, and polymyxin B sulfate appear to be well tolerated whereas cephalexin monohydrate and penicillin G caused a repeated pattern of significant CSF pleocytosis, histological evidence of periventricular perivascular infiltrates, and evidence of clinical toxicity. A regime for treatment of central nervous system infections is presented, derived from the data presented above. Preliminary experience in a clinical series appears to support this program.