Penicillin concentrations in cerebrospinal fluid after different treatment regimens for syphilis

Outcomes From Re-Treatment and Cerebrospinal Fluid Analyses in Patients With Syphilis Who Had Serological Nonresponse or Lack of Seroreversion After Initial Therapy

BACKGROUND

We conducted an observational study to determine whether patients with syphilis who do not demonstrate serological cure or lack of seroreversion in nontreponemal (NT) antibody titers after initial therapy benefit from re-treatment and cerebrospinal fluid (CSF) analysis.

METHODS

We enrolled patients with syphilis from sexually transmitted disease clinics in Guangzhou, China, who had persistent NT titers after therapy. Serological nonresponse was defined as a <4-fold decline in baseline NT titers after therapy. Lack of seroreversion was defined as demonstrating a ≥4-fold NT titer decline but without seroreversion to negative, or having persistent low-level titers (i.e., 1:1-1:2) after therapy. After consent, we abstracted medical record data regarding syphilis diagnoses, initial and re-treatment regimens, and serological outcomes. Nontreponemal titers were obtained from participants at enrollment and follow-up. We evaluated CSF findings among a subgroup of participants relative to re-treatment.

RESULTS

From March 2012 to February 2016, we enrolled 135 HIV-negative patients with syphilis with persistent NT titers after initial therapy. Among 116 participants with ≥12 months of follow-up, 60 (52%) received re-treatment of syphilis. Overall, there were no significant differences in serological response between those who were re-treated and those who were not among serological nonresponders (29% vs. 27%; P = 1.0) or among participants without seroconversion (41% vs. 37%; P = 0.8). Of 60 participants who underwent CSF analyses, 8 (13%) had CSF abnormalities, but only 2 (3%) met the neurosyphilis criteria after re-treatment.

CONCLUSIONS

Most HIV-negative patients with syphilis who have serological nonresponse or lack of seroreversion after therapy do not benefit from re-treatment in the short term, and neurosyphilis is uncommon.

Neurosyphilis in HIV-infected patients

A review article is addressed the issue of the diagnosis and treatment of neurosyphilis that is developing against the background of HIV-infection. HIV-infected patients are at higher risk of neurologic, ocular and auricular manifestation of syphilis as well as treatment failures and relapses. Diagnosis of neurosyphilis in HIV-positive patients is complicated because both infections cause similar changes in the cerebrospinal fluid (CSF). The effectiveness of neurosyphilis treatment in patients with HIV co-infection is difficult to estimate, since the normalization of their CSF goes slower comparing to HIV-negatives. The increase in incidence of syphilis and HIV co-infection is anticipated in the coming years. This necessitates a comprehensive study of the problem and requires the development of new approaches to neurosyphilis diagnosis and treatment in co-infected patients.

A single dose of benzathine penicillin G is as effective as multiple doses of benzathine penicillin G for the treatment of HIV-infected persons with early syphilis

BACKGROUND

Treatment guidelines recommend the use of a single dose of benzathine penicillin G (BPG) for treating early syphilis in human immunodeficiency virus (HIV)-infected persons. However, data supporting this recommendation are limited. We examined the efficacy of single-dose BPG in the US Military HIV Natural History Study.

METHODS

Subjects were included if they met serologic criteria for syphilis (ie, a positive nontreponemal test [NTr] confirmed by treponemal testing). Response to treatment was assessed at 13 months and was defined by a ≥4-fold decline in NTr titer. Multivariate Cox proportional hazard regression models were utilized to examine factors associated with treatment response.

RESULTS

Three hundred fifty subjects (99% male) contributed 478 cases. Three hundred ninety-three cases were treated exclusively with BPG (141 with 1 dose of BPG). Treatment response was the same among those receiving 1 or >1 dose of BPG (92%). In a multivariate analysis, older age (hazard ratio [HR], 0.82 per 10-year increase; 95% confidence interval [CI], .73-.93) was associated with delayed response to treatment. Higher pretreatment titers (reference NTr titer <1:64; HR, 1.94 [95% CI, 1.58-2.39]) and CD4 counts (HR, 1.07 for every 100-cell increase [95% CI, 1.01-1.12]) were associated with a faster response to treatment. Response was not affected by the number of BPG doses received (reference, 1 dose of BPG; HR, 1.11 [95% CI, .89-1.4]).

CONCLUSIONS

In this cohort, additional BPG doses did not affect treatment response. Our data support the current recommendations for the use of a single dose of BPG to treat HIV-infected persons with early syphilis.

REVIEW: Neurosyphilis: A historical perspective and review

Treponema pallidum subspecies pallidum, the causative agent of syphilis, disseminates to the central nervous system within days after exposure. Clinical manifestations can occur during any stage of the infection, and include asymptomatic neurosyphilis, acute meningeal syphilis, meningovascular syphilis, paretic neurosyphilis, and tabetic neurosyphilis. The majority of cases are reported in HIV-infected patients but the epidemiology of modern neurosyphilis is not well defined because of the paucity of population-based data. Decreasing reports of late neurosyphilis have been countered with increasing reports of early neurologic involvement. This review summarizes the clinical manifestations, diagnosis, and therapy of neurosyphilis, focusing on areas of continued controversy, and highlighting several important questions that remain unanswered. Since 2000, the rates of syphilis continue to increase. Given the effectiveness of penicillin therapy, these trends suggest a failure of prevention. Regrettably, rather than become an infection of historical significance, syphilis in the era of HIV continues to challenge researchers and clinicians.

Update on neurosyphilis

Neurosyphilis literally means syphilitic infection of the central nervous system, but it is often referred to incorrectly as "tertiary syphilis." Neurosyphilis can occur at any time in the course of syphilis, even in the earliest, primary, stage. Early forms of neurosyphilis primarily affect the meninges, cerebrospinal fluid, and cerebral or spinal cord vasculature. Late forms of neurosyphilis primarily affect the brain and spinal cord parenchyma. Uveitis and hearing loss related to syphilis are most common in early syphilis and may be accompanied by early neurosyphilis. The treatment for syphilis-related eye disease and hearing loss is the same as the treatment for neurosyphilis. Neurosyphilis is more commonly seen in patients infected with HIV, and much of the recent literature pertains to this risk group. This article provides a critical review of recent literature on the diagnosis, clinical findings, risk factors, and management of neurosyphilis.

Antibiotics for syphilis diagnosed during pregnancy

BACKGROUND

Congenital syphilis is an increasing problem in many developing countries and in the transitional economies of Eastern Europe and the former Soviet Union. In several countries this increase has been aggravated by HIV/AIDS. While the effectiveness of penicillin in the treatment of syphilis in pregnant women and the prevention of congenital syphilis was established shortly after the introduction of penicillin in the 1940s, there is uncertainty about the optimal treatment regimens.

OBJECTIVES

To identify the most effective antibiotic treatment regimen (in terms of dose, length of course and mode of administration) of syphilis with and without concomitant infection with HIV for pregnant women infected with syphilis.

SEARCH STRATEGY

MEDLINE 1966 to March 2000; EMBASE 1974 to March 2000, the Cochrane Controlled Trials Register (last searched March 2001), the Cochrane Pregnancy and Childbirth group trials register (last searched March 2001) and the references of traditional reviews were searched. Experts in specialist units were contacted.

SELECTION CRITERIA

It was planned that any trial in which an attempt is made to allocate treatment for syphilis during pregnancy by a random or quasi-random method would be included in this review.

DATA COLLECTION AND ANALYSIS

Information was extracted using a data extraction sheet and this included entry criteria, the source of controls, and whether the authors stratified by the stage of pregnancy when the diagnosis of syphilis was made.

MAIN RESULTS

Twenty six studies met the criteria for detailed scrutiny. However, none of these met the pre-determined criteria for comparative groups and none included comparisons between randomly allocated groups of pregnant women.

REVIEWER'S CONCLUSIONS

While there is no doubt that penicillin is effective in the treatment of syphilis in pregnancy and the prevention of congenital syphilis, uncertainty remains about what are the optimal treatment regimens. Further studies are needed to evaluate treatment failure cases with currently recommended regimens and this should include an assessment of the role of HIV infection in cases of prenatal syphilis treatment failure. The effectiveness of various antibiotic regimens for the treatment of primary and secondary syphilis in pregnant women need to be assessed using randomised controlled trials which compare them with existing recommendations.

Controversies in the use of antimicrobials for the prevention and treatment of Lyme disease

Unanswered questions in the management of patients with Lyme disease or those who have had Ixodes tick bites include: Is antimicrobial therapy effective in preventing Lyme disease during the incubation period of the infection? Which oral agents are most effective in treatment of Lyme disease? Are macrolides efficacious? And, for how long a time period should antimicrobial therapy be given? Potentially useful insights into these questions can be gained by examining experience with other spirochetal infections. Using this information, in conjunction with existing data from recent studies on Lyme borreliosis, tentative answers to these questions can be formulated. Based on this analysis, it would be anticipated that a short course of antibiotic therapy, perhaps even a single dose, will be effective in preventing Lyme disease after a tick bite. Beta-lactam antibiotics such as amoxicillin, and tetracycline preparations, such as doxycycline, are the mainstays of oral therapy for treatment of active infection. Macrolides are less effective, but their utility is likely to be improved if they are given in maximal dosage. There is no convincing evidence for extending treatment of early Lyme disease beyond 14 days. There is also no evidence that longer therapy is more efficacious for other manifestations of Lyme disease, although this issue deserves further study.

Treating Syphilis: Examining therapeutic approaches to this STD

Background information on treating syphilis indicates that some currently recommended approaches to therapy are not optimal. There is no perfect drug schedule available, but penicillin remains the drug of choice. The author's recommendations for treatment and follow up are presented.

Solubilization and stabilization of a benzylpenicillin chemical delivery system by 2-hydroxypropyl-beta-cyclodextrin

A dihydropyridine----pyridinium salt redox carrier-based chemical delivery system for benzylpenicillin (1) was complexed with 2-hydroxypropyl-beta-cyclodextrin (HPCD). The solubility of the lipophilic 1, which is incompatible with aqueous formulations, was dramatically increased and showed a linear dependency on the HPCD concentration. The degree of incorporation was 20 mg of 1 per g of complex. The stability study of 1 in various pH buffers indicated the base-catalyzed hydrolysis of the acyloxyalkyl linkage and the hydration of the 5,6 double bond of the dihydropyridine as the main degradation processes. The overall loss of 1, which follows first-order kinetics, was not influenced by changes in ionic strength and elimination of oxygen from the reaction medium. The HPCD complex of 1, which has a stability constant of 720-940 M-1, stabilized the chemical delivery system. The influence of the temperature on the stability of 1 is also discussed.

Modern neurosyphilis--a critical analysis

Neurosyphilis remains a source of perplexity for today's physicians. Controversies exist over the interpretation of serologic tests, cerebrospinal fluid (CSF) abnormalities, diagnostic criteria, and treatment regimens. Its occurrence with human immunodeficiency virus (HIV) infection has raised fears of its recrudescence. A critical analysis of the evidence behind these viewpoints leads to several conclusions: the CSF VDRL is the most appropriate diagnostic test; pleocytosis is the only reliable CSF measure of disease activity; commonly accepted diagnostic criteria do not exclude nonsyphilitic disease; and treatment requires the prolonged use of parenteral penicillin, but no superior regimen has been found. Most data do not currently support the view that concurrent HIV infection produces accelerated or resistant neurosyphilis.

Effect of early and late syphilis on central nervous system: cerebrospinal fluid changes and neurological deficit

Neurological examination and investigation of the cerebrospinal fluid (CSF) was performed on 24 patients with early and 180 patients with late syphilis. In 21 (12%) patients with late syphilis positive CSF treponemal test results and neurological deficits suggestive of symptomatic neurosyphilis were found. Concomitantly all but three patients with neurosyphilis showed one or more of the following abnormal CSF variables: CSF concentration of albumin X 10(3)/serum concentration (albumin ratio) greater than or equal to 7.9; mononuclear cells greater than 5 microliters: ratio of CSF to serum IgG concentrations/ratio of CSF to serum albumin concentrations (IgG index) greater than or equal to 0.7 or of IgM/albumin (IgM index) greater than or equal to 0.1; or oligoclonal CSF immunoglobulins. In 20 (95%) patients with neurosyphilis evidence of the production of treponemal antibodies within the central nervous system (CNS) was shown. Ten (48%) patients with neurosyphilis had been treated previously for late syphilis. These observations emphasise the need to screen for neurosyphilis in patients with late syphilis. Intrathecal production of treponemal antibodies was detected in six (25%) patients with early and 44 (28%) with late syphilis who did not show any neurological deficit. Intrathecal production of treponemal antibodies indicating that the CNS was affected led us to suspect asymptomatic neurosyphilis in these patients. Seventeen (11%) patients with late syphilis but no neurosyphilis and only one (4%) with early syphilis showed additional abnormal CSF variables. Surprisingly, six out of 22 patients with treated early and 20 out of 68 patients with treated late syphilis showed evidence of treponema antibody production within the CNS. We do not know whether these findings indicate that the CNS was affected because of inadequate treatment or merely reflect persistent synthesis of treponemal antibodies associated with cured infection. In one (4%) patient with early and in 21 (13%) with late syphilis but no neurosyphilis abnormal CSF variables in the absence of positive CSF treponemal test results were observed, which excluded syphilitic inflammation of the CNS.

Survival of treponemes after treatment: comments, clinical conclusions, and recommendations

Treponemes may persist after treatment that has been accepted as effective; the reasons for this are discussed. Nevertheless, the epidemic of syphilis after the second world war was not followed by an epidemic of late syphilis, and the results of treatment with penicillin are excellent. Neurological signs may progress in some treated patients, and the standard doses of soluble penicillin and any dose of benzathine penicillin (even with added probenecid by mouth) cannot be relied on to achieve treponemicidal concentrations in the cerebrospinal fluid (CSF). There are no large scale studies of CSF findings after treatment of early syphilis with benzathine penicillin. Standard dosage, such as procaine penicillin G 600 000 international units (IU) by intramuscular injection for 10 days, is the treatment of choice for the patient suffering from uncomplicated early syphilis; this should be preferred to benzathine penicillin, which should only be used when standard treatment as above cannot be given. Treponemicidal concentrations of penicillin should be achieved in the CSF of patients suffering from neurosyphilis by schedules of probenecid by mouth and procaine penicillin by single daily intramuscular injections; treatment should last for 17 to 21 days. Benzathine penicillin should not be used for the treatment of patients suffering from neurosyphilis or from the iritis of late syphilis including that accompanying interstitial keratitis. Treatment for interstitial keratitis should initially be as for neurosyphilis, but in recurrent cases it may have to be prolonged to eradicate Treponema pallidum that is dividing slowly. Doxycycline 200 mg by mouth daily for 21 days provides a supervisable outpatient schedule for patients allergic to penicillin. Cephaloridine (and probably cefuroxime and the new cephalosporins) may be useful for patients who are allergic to penicillin but have not developed anaphylactic allergy. If erythromycin is used for treating syphilis in pregnant women who are allergic to penicillin, then the newborn babies should be treated with penicillin.

Preventing complications of sexually transmitted disease. New treatment guidelines for an expanded spectrum of problems

Newly recognised sexually transmitted diseases have combined with the traditional venereal diseases to present clinicians with a demanding management challenge. Besides the increases in incidence of some of these diseases, many of the associated organisms are becoming more resistant to commonly used antimicrobial drugs. Predictably, accompanying this trend are increasing numbers of serious complications affecting men, women and infants. Timely and appropriate management of patients presenting with sexually transmitted diseases are imperative to stem the swelling tide of these conditions and prevent their insidious consequences. Clinicians must therefore remain knowledgeable about the effective therapies (and regimens) that are available. An update of the treatment guidelines for sexually transmitted diseases is provided in this article. As well as selecting appropriate antimicrobial regimens, it is equally important that clinicians educate their patients about their disease and its probable course, explain the administration of medications clearly to patients, and follow them up appropriately to detect resistant cases and non-compliers, and ultimately ensure effective treatment. In addition, no patient should be considered appropriately managed until his or her sexual partners have been properly dispositioned. For most patients, this will entail examining their sexual partners and treating them immediately. Execution of these treatment guidelines and management principles will help protect the reproductive capability of many women by preventing pelvic inflammatory disease, ectopic pregnancy, and infertility.

Clinical pharmacokinetics of cerebrospinal fluid

The distribution of drugs into the cerebrospinal fluid has long been considered a challenging field of investigation in 2 major respects: (a) understanding how the physicochemical properties (molecular weight, pKa, plasma protein binding) of various molecules influence their movements across such a specific structure as the blood-brain barrier; and (b) defining the relationship between cerebrospinal fluid concentrations of various drugs and their central (side) effects. An attempt has been made to review the very dispersed information presently available to offer a clinically orientated picture of this area of pharmacokinetics. Drugs acting on the central nervous system (benzodiazepines, tricyclic antidepressants, anticonvulsants, opioids), antibacterial agents, cardiovascular drugs (beta-adrenoceptor blockers and digoxin), antineoplastic drugs (mainly methotrexate), and other miscellaneous agents (corticosteroids, cimetidine, methylxanthines) are reviewed. The available evidence seems to support the conclusion that only for methotrexate and antibacterial agents does knowledge of cerebrospinal fluid pharmacokinetics have direct therapeutic implications, while the mosaic of information available for other drugs does little more than provide a partially satisfactory picture.

Treatment of syphilis

THE RESULTS OF THE TREATMENT OF EARLY SYPHILIS WITH PENICILLIN HAVE BEEN EXCELLENT: patients are rendered non-infectious within hours, sero-reversal to tests with lipid antigens occurs within months and insignificant numbers of patients with cardiovascular or neurosyphilis are found among those who have received adequate treatment. On the other hand, seropositivity to tests with treponemal antigens may persist, sometimes indefinitely, and reinfections are, today, by no means uncommon. The physician also has a responsibility to persuade the patient with early infectious syphilis to induce the person who was the source of the infection and subsequent sexual partners to undergo examination and treatment.In late syphilis, no treatment can repair structural damage that has already occurred, e.g., severed neurons in the nervous system or loss of elastic tissue in the aortic wall, and clinical progression may occur in spite of treatment. Nevertheless, penicillin provides the basis of therapy.Early congenital syphilis, like the acquired infection, responds well to penicillin. However, because benzathine penicillin penetrates poorly into the cerebrospinal fluid much higher doses of procaine penicillin are now recommended, or alternatively the use of crystalline penicillin G.A recent WHO Scientific Group on Treponemal Infections has made new recommendations concerning the treatment of syphilis and these will be considered by the next WHO Expert Committee on Venereal Diseases, Treponematoses and Neisseria infections. Some of these recommendations are outlined in this article.