Association between non-injection drug use and hepatitis C infection among HIV-negative men who have sex with men

BACKGROUND

Prior research predominantly examined the association between HIV-positive men who have sex with men (MSM) or those using injection drugs and hepatitis C virus (HCV) infection. However, limited attention has been given to understanding the association among HIV-negative MSM who do not inject drugs. This gap leaves apportion of the population unexamined, potentially overlooking important factor that may contribute to the transmission and prevalence of HCV. This study aims to investigate the relationship between non-injection drug use and HCV infection in this population.

METHODS

In this cross-sectional study, we analyzed data on 118 MSM who reported use of non-injection drugs. The participants were recruited from two inner-city communities in Houston, TX, between 2004 and 2007 and were negative for both HIV and hepatitis B virus infection. Latent class analysis (LCA) was used to identify drug use latent classes. Multinomial logistic regression analysis was used to evaluate the association between drug use latent class and HCV infection.

RESULTS

Four distinct latent classes of drug use were identified: class 1, persons ≥ 42 years of age who used only crack cocaine; class 2, persons approximately 42 years of age who used > 2 drugs; class 3, persons < 42 years of age who used > 5 drugs; and class 4, persons ≥ 42 years of age who used > 6 drugs. Class 4 was significantly associated with HCV infection. The odds of HCV infection in members of class 4 was 17 times higher than in class 2 members (adjusted odds ratio [aOR] = 16.9, 95% confidence interval [CI]: 1.4-205.4) and almost 22 times higher than in class 3 members (aOR = 21.8, 95% CI: 1.5-322.8).

CONCLUSIONS

Among MSM with non-injection drug use, the subgroup of individuals who were ≥ 42 years of age and used multiple drugs (including heroin, speedball, methamphetamine, crack cocaine, and marijuana) had a high probability of HCV infection. Public health and education programs, as well as drug treatment and rehabilitation programs, should be developed for this high-risk subgroup of individuals to prevent HCV acquisition and transmission.

Orbital Complication in the Setting of Cocaine Use: A Case Report and Review of Literature

Orbital cellulitis is a common ophthalmologic consultation and has numerous risk factors; however, one that is seldomly encountered is chronic cocaine use. We describe a case of a 63-year-old man with a history of HIV and cocaine use who presented with OD pain, proptosis, and blurred vision. CT imaging revealed extensive erosions throughout the nasal septum, bilateral turbinates, ethmoid sinuses, and loss of the right medial orbital wall. The patient was treated empirically with broad-spectrum antibiotics, and a nasal biopsy and culture grew Staphylococcus aureus. After treatment with IV antibiotics, the patient's visual acuity returned to baseline with resolution of extraocular motility limitations. Although nasal erosions are a well-described sequela of cocaine use, full-thickness osseous defects of the orbital wall are rare and represent late-stage complications of cocaine-induced destructive midline lesions. Orbital cellulitis is a very rare complication in the setting of cocaine-induced destructive midline lesions. Clinicians should be aware of the link between cocaine use, rhino-orbital abnormalities, and orbital cellulitis.

Cocaine- and Levamisole-Induced Vasculitis: Defining the Spectrum of Autoimmune Manifestations

Drug-induced or associated vasculitis is a prevalent form of vasculitis that resembles primary idiopathic antineutrophil cytoplasmic autoantibody (ANCA) vasculitis (AAV). Cocaine is a diffuse psychostimulant drug and levamisole is a synthetic compound used to cut cocaine. Their abuse may result in a spectrum of autoimmune manifestations which could be categorized into three overlapping clinical pictures: cocaine-induced midline destructive lesion (CIMDL), levamisole-adulterated cocaine (LAC) vasculopathy/vasculitis, and cocaine-induced vasculitis (CIV). The mechanisms by which cocaine use leads to disorders resembling AAV are not well understood. Cocaine can cause autoimmune manifestations ranging from localized nasal lesions to systemic diseases, with neutrophils playing a key role through NETosis and ANCA development, which exacerbates immune responses and tissue damage. Diagnosing and treating these conditions becomes challenging when cocaine and levamisole abuse is not suspected, due to the differences and overlaps in clinical, diagnostic, therapeutic, and prognostic aspects compared to primary idiopathic vasculitides.

Oral Rehabilitation for a Patient with Cocaine-Induced Midline Destructive Lesions

Background

Cocaine is the second most consumed drug worldwide, more than 0.4% of the global population, and has become a real public health problem in recent years. Its inhalation causes significant centrofacial lesions, grouped under the name cocaine-induced midline destructive lesion (CIMDL). These destructions are due to the conjunction of the vasoconstrictor, local prothrombogenic effects, and cytotoxic effects of cocaine. The ischemia produced by this substance is due to vasoconstriction that leads to nasal tissue necrosis and perforation of the nasal septum secondary to chondral necrosis. Case Presentation. A 36-year-old man, previously grappling with cocaine addiction, was hospitalized to undergo comprehensive clinical, microbiological, and radiological examinations because he was suffering from the emergence of crusts and ulceration in the nasal mucosa, accompanied by a palate perforation, a 39°C fever, and chills. Standard bacteriological culture was positive for coagulase-negative staphylococci and Escherichia coli, while mycological culture was positive for Candida tropicalis. The CT scan images of the sinuses confirmed the presence of palatal perforation and total destruction of the nasal septum, cartilaginous portion, maxillary sinus medial wall, lower and middle turbinates, and middle meatus. Nasal endoscopy revealed an exposition of the bony wall and displayed the exposition of the occipital bone's clivus. A diagnosis of CIMDL was confirmed. Antibiotic therapy was decided based on antibiogram results by the consulting microbiologist. Debridement of necrotic tissue was done by nasal endoscopy with local cleaning and was repetitive during the first week to maintain the best cleanliness possible. The patient was discharged with oro-nasal hygiene instructions and referred for prosthetic rehabilation. As for the cocaine addiction, the patient was in follow-up with a psychologist in a specialized centre.

Conclusion

The care is multidisciplinary. Psychological help and assistance are essential to guide patients to become cocaine free and to avoid a relapse. Weaning is a prerequisite for surgery. Rehabilitation of speech and swallowing is necessary. Many local flaps or micro-anastomoses are possible.

International consensus statement on allergy and rhinology: Allergic rhinitis - 2023

BACKGROUND

In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document.

METHODS

ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work.

RESULTS

ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost.

CONCLUSION

The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

Gene Expression Analysis in Patients with Cocaine-Induced Midline Destructive Lesions

BACKGROUND AND OBJECTIVES

Cocaine users may present with positive antineutrophil cytoplasmic antibodies (ANCA) and severe midline destructive lesions (CIMDL) which are histologically characterized by massive apoptosis. However, histopathological and laboratory studies suggest that autoimmunity may not be the main pathogenic driver. We analyzed gene expression both in cell lines of nasal mucosa exposed to cocaine and in CIMDL patients to determine whether genetic predisposition might cause such lesions, which are observed in a minority of cocaine abusers.

MATERIALS AND METHODS

The genetic expression profile of nasal mucosa exposed to cocaine was analyzed. Rare variants of expressed genes were searched in patients with CIMDL using exome sequencing and bio-informatics.

RESULTS

We identified 462 genes that were induced by cocaine, mainly related to apoptosis and autophagy in response to oxidative stress. Under the hypothesis that genes linked to the phenotype are also induced by cocaine itself, a rare variants burden test was performed to select genes that were significantly enriched in rare mutations. Next, 11 cocaine abusers with CIMDL and no other relevant medical comorbidities underwent exome sequencing, and 12 genes that were significantly enriched in the burden test and present in at least 10 patients were identified. An in-depth analysis of these genes revealed their involvement in apoptosis, tissue homeostasis, autophagy, and response to oxidative stress.

CONCLUSIONS

Oxidative stress and rare genetic alterations in the response to reactive oxygen species, apoptosis, autophagy, and tissue regeneration are plausible drivers of damage affecting nasal mucosa exposed to cocaine crystals and, consequently, the pathogenic mechanism behind CIMDL.

Cocaine-Induced Midline Destructive Lesions: A Real Challenge in Oral Rehabilitation

Cocaine abuse is associated with severe local effects on mucosal and osteocartilaginous structures, with a centrifugal spreading pattern from the nose, a condition known as cocaine-induced midline destructive lesions (CIMDL). When the soft or hard palate is affected, a perforation may occur, with subsequent oro-nasal reflux and hypernasal speech. Both diagnosis and therapy (surgical or prosthetic) constitute a serious challenge for the physician. The cases of three patients affected by cocaine-induced palatal perforation and treated with a palatal obturator at San Raffaele Dentistry department between 2016 and 2019 are presented. In addition, the literature was reviewed in search of papers reporting the therapeutic management in patients affected by cocaine-induced palatal perforation. All the patients in our sample suffered from oro-nasal reflux and hypernasal speech, and reported a significant impact on interpersonal relationships. The results at the delivery of the obturator were satisfactory, but the duration of such results was limited in two cases, as the progression of the disease necessitated continuous modifications of the product, with a consequent increase in costs and a reduction in patient satisfaction. In conclusion, the therapy for palatal defects in CIMDL includes both reconstructive surgery and prosthetic obturators, the latter being the only possibility in the event of active disease. It successfully relieves symptoms, but the long-term efficacy is strongly related to the level of disease activity.

IgG4-Related Disease of the Oral Cavity. Case Series from a Large Single-Center Cohort of Italian Patients

A series of destructive and tumefactive lesions of the oral cavity are increasingly recognized as part of the IgG4-related disease (IgG4-RD) spectrum. We herein examined the clinical, serological, radiological, and histological features of a series of patients referred to our clinic because of oral cavity lesions ultimately attributed to IgG4-RD. In particular, we studied 6 consecutive patients out of 200 patients referred to the immunology outpatient unit who presented with erosive and/or tumefactive lesions of the oral cavity. All patients underwent serum IgG4 measurement, nasal endoscopy, radiological studies, and histological evaluation of tissue specimens. The histological studies included immunostaining studies to assess the number of IgG4+ plasma cells/High-Power Field (HPF) for calculation of the IgG4+/IgG+ plasma cell ratio. Six patients (3% of the entire cohort) were diagnosed with IgG4-RD of the oral cavity based on histological evaluation. A major complaint at presentation was oral discomfort due to bulging mass. A mild to no increase in serum IgG4 was observed. Different patterns of organ involvement were associated with oral lesions. Five patients were treated with immunosuppressive therapy and two patients promptly responded to B-cell depletion with rituximab. Watchful waiting was decided in one patient with no major clinical symptoms. Involvement of the oral cavity is an infrequent manifestation of IgG4-RD but should be taken into consideration as a possible differential diagnosis of tumefactive or erosive lesions once neoplastic conditions are excluded. A histological examination of biopsy samples from the oral cavity represents the mainstay for diagnosis of IgG4-RD.

Cocaïne et lésions destructrices centro-faciales : à propos d'un cas

INTRODUCTION

Cocaine use is associated with multiple complications, some of which can mimic systemic diseases, especially Antineutrophil Cytoplasmic Antibody (ANCA) associated vasculitis. We report a case of Cocaine Induced Midline Destructive Lesions (CIMDL) for which a diagnosis of granulomatosis with polyangiitis (GPA) was discussed.

CASE REPORT

A 42-year-old male, cocaine consumer, was admitted in our department for a centrofacial destructive process. He had no extra ear, nose and throat (ENT) involvement. ANCA were positive with a perinuclear fluorescence pattern and an anti-Proteinase 3 specificity. Regarding this unusual immunologic pattern and in the absence of histological argument for a GPA, a diagnosis of CIMDL was made.

CONCLUSION

CIMDL is a centrofacial destructive process due to intranasal cocaine use. It is frequently associated with the presence of p-ANCA with both anti-HNE and anti-PR3 specificity.

International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis

BACKGROUND

Critical examination of the quality and validity of available allergic rhinitis (AR) literature is necessary to improve understanding and to appropriately translate this knowledge to clinical care of the AR patient. To evaluate the existing AR literature, international multidisciplinary experts with an interest in AR have produced the International Consensus statement on Allergy and Rhinology: Allergic Rhinitis (ICAR:AR).

METHODS

Using previously described methodology, specific topics were developed relating to AR. Each topic was assigned a literature review, evidence-based review (EBR), or evidence-based review with recommendations (EBRR) format as dictated by available evidence and purpose within the ICAR:AR document. Following iterative reviews of each topic, the ICAR:AR document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:AR document addresses over 100 individual topics related to AR, including diagnosis, pathophysiology, epidemiology, disease burden, risk factors for the development of AR, allergy testing modalities, treatment, and other conditions/comorbidities associated with AR.

CONCLUSION

This critical review of the AR literature has identified several strengths; providers can be confident that treatment decisions are supported by rigorous studies. However, there are also substantial gaps in the AR literature. These knowledge gaps should be viewed as opportunities for improvement, as often the things that we teach and the medicine that we practice are not based on the best quality evidence. This document aims to highlight the strengths and weaknesses of the AR literature to identify areas for future AR research and improved understanding.

Huge lipoma of the right parotid gland: Case report and review of 42 cases

Lipomas are rarely found in the parotid gland region. Because of their rarity at this site, they are not often considered in the differential diagnosis of parotid tumors. The parotid lipoma is a slowly growing, asymptomatic, freely movable, soft mass. Preoperative diagnosis is generally difficult. We present a case of a slowly enlarging mass of the parotid region in a 44-year-old man that proved to be a lipomatous tumor of the parotid gland. We also review 42 other cases from the literature. Our patient's huge tumor was located in the superficial lobe of the gland, and a parotidectomy with preservation of the facial nerve was performed. There was no complication or recurrence of the tumor after a follow-up of 1 year.

Craniovertebral junction instability as an extension of cocaine-induced midline destructive lesions: case report

With the increasingly widespread illicit use of cocaine, a broad spectrum of clinical pathologies related to this form of drug abuse is emerging. The most frequently used method of administration of powdered cocaine is intranasal inhalation, or "snorting." Consequently, adverse effects of cocaine on the nasal tract are common. Habitual nasal insufflations of cocaine can cause mucosal lesions. If cocaine use becomes chronic and compulsive, progressive damage of the mucosa and perichondrium leads to ischemic necrosis of the septal cartilage and perforation of the nasal septum. Occasionally, cocaine-induced lesions cause extensive destruction of the osteocartilaginous structures of the nose, sinuses, and palate and can mimic other diseases such as tumors, infections, and immunological diseases. In the literature currently available, involvement of the craniovertebral junction in the cocaine-induced midline destructive lesions (CIMDLs) has never been reported. The present case concerns a 44-year-old man who presented with long-standing symptoms including nasal obstruction, epistaxis, dysphagia, nasal reflux, and severe neck pain. A diagnosis of CIMDL was made in light of the patient's history and the findings on physical and endoscopic examinations, imaging studies, and laboratory testing. Involvement of the craniovertebral junction in the destructive process was evident. For neurosurgical treatment, the authors considered the high grade of atlantoaxial instability, the poorly understood cocaine-induced lesions of the spine and their potential evolution overtime, as well as cocaine abusers' poor compliance. The patient underwent posterior craniovertebral fixation. Understanding, classifying, and treating cocaine-induced lesions involving the craniovertebral junction are a challenge.

Expression of Apoptosis Mediators p53 and Caspase 3, 7, and 9 in Chronic Rhinosinusitis with Nasal Polyposis

Background

The causal factor for the perpetuation of the inflammatory process in chronic rhinosinusitis with nasal polyps (CRSwNPs) has been extensively studied. However, little is known about the influence of cell death in this disease. Thus, the molecular assessment of mechanisms involved in apoptosis might shed light on the pathogenesis of CRSwNPs. This study was designed to evaluate the gene expression of different apoptotic factors in patients with NPs compared with control patients.

Methods

The mRNA expression of the apoptosis mediators caspase 3, 7, and 9 and of p53 protein was analyzed using quantitative reverse transcription–polymerase chain reaction in 25 NPs and 18 control samples.

Results

We observed significantly lower expression of p53 and caspase 3 and 9 in patients with CRSwNPs compared with the controls, whereas caspase 7 expression was not significantly different from the controls.

Conclusion

The reduced expression of these apoptosis factors in CRSwNPs might be related to higher proliferation and the perpetuation of inflammatory cells hindering the control of the disease. A better understanding of the possible influence of apoptosis factors on CRSwNPs could provide rationale for future therapies.

Prevalence of hepatitis C in a Swiss sample of men who have sex with men: whom to screen for HCV infection?

BACKGROUND

While the numbers of hepatitis-C-virus (HCV) infections among men who have sex with men (MSM) who are co-infected with the human immunodeficiency virus (HIV) are on the rise, with vast evidence for sexual transmission of HCV in this population, concerns have also been raised regarding sexual HCV-transmission among MSM without HIV infection. Therefore, the aim of this study was to estimate the prevalence of hepatitis C among MSM without HIV diagnosis in Zurich (Switzerland).

METHODS

Participants were recruited from a gay health centre and various locations such as dark rooms, saunas and cruising areas in Zurich. Participants self-completed a questionnaire assessing known and suspected risk factors for HCV-infection, and provided a blood sample for detection of past (antibodies) and present (core antigen, RNA) infections with HCV.

RESULTS

In total, 840 MSM aged 17-79 (median: 33 years) underwent HCV-testing and completed the questionnaire, among whom 19 reported living with HIV. Overall, seven tested positive for HCV-antibodies, and two were also positive for HCV core antigen and HCV-RNA-these two were immigrants, one from a country where HCV is endemic. None of the seven were aware of their infection. The seroprevalence of hepatitis C among the 821 non-HIV-diagnosed MSM was 0.37% (95%-CI: 0.12-1.69%), and one man harboured replicating virus (0.12%; 0.02-0.69%), resulting in a number needed to test of 821 to detect one active infection. Significant univariable associations of lifetime HCV-infection were found with known HIV-diagnosis (OR=72.7), being tattooed (OR=10.4), non-injection use of cocaine/amphetamines (OR=8.8), and non-Swiss origin (OR=8.5). For MSM without HIV-diagnosis, the only variable marginally associated with positive HCV-serostatus was being tattooed (OR=8.3). No significant associations were observed with reported injection drug use, unprotected anal intercourse, sexual practices that may lead to mucosal trauma, or proxy measures for group sex and lesion-prone STIs.

CONCLUSIONS

Our findings suggest that in Switzerland, hepatitis C among MSM without diagnosed HIV is not more prevalent than in the general population. We found no evidence of elevated rates of sexual transmission of HCV among MSM without HIV-infection. Therefore, we currently see no reason for promoting HCV-testing among all MSM in Switzerland.

The manifestation of cocaine-induced midline destructive lesion in bone tissue and its identification in human skeletal remains

Cocaine-induced midline destructive lesion (CIMDL) is a condition that may arise in response to chronic insufflation ("snorting") of cocaine. It is clinically diagnosed when the nasal septum, lateral nasal walls, and/or hard palate show signs of destruction in association with cocaine use. Although its true incidence is unknown, CIMDL is not an uncommon clinical finding amongst intranasal cocaine abusers and is likely to be encountered by forensic anthropologists and medical examiners working worldwide. Given the preponderance of drug abusers amongst the subjects of forensic casework, the ability to diagnose CIMDL in dry bone may provide crucial insight into an investigation and even help confirm an individual identification. This paper aims to make practicing forensic anthropologists aware of CIMDL. Through the analysis of existing clinical literature, patient CT scans, and histology sections, it works toward the establishment of formal diagnostic criteria for identifying CIMDL in human skeletal remains. Lytic destruction regularly involves the vomer and frequently extends to the perpendicular plate of the ethmoid, the palatal process of the maxillae or the palatine bones, and the inferior nasal conchae. The middle nasal conchae, medial walls of the maxillary sinuses, ethmoid sinuses, and cribriform plate are often damaged. Destruction may also implicate the superior nasal conchae, the orbit, and the sphenoid. Bones affected by CIMDL may contain necrotic lesions or may be absent entirely. Lesions show minimal, if any, signs of repair. The author proposes that this lack of new bone formation may be mediated by potentially elevated leptin levels in cocaine abusers and CIMDL patients and may be the key to differentiating CIMDL from other lytic processes of the midface.

Cocaine-induced midline destructive lesions - an autoimmune disease?

In Europe it is estimated that around 13million of adults (15-64years) have used cocaine at least once in their lifetime. The most frequently used route of administration for the drug is intranasal inhalation, or "snorting", and thus the adverse effects of cocaine on the nasal tract are very common. Habitual nasal insufflations of cocaine may cause mucosal lesions, and if cocaine use becomes chronic and compulsive, progressive damage of the mucosa and perichondrium leads to ischemic necrosis of septal cartilage and perforation of the nasal septum. Occasionally, cocaine-induced lesions cause extensive destruction of the osteocartilaginous structures of nose, sinuses and palate that can mimic other diseases such as tumors, infections, and immunological diseases. Thorough diagnostic workup, including endoscopic, radiologic, histopathologic and serologic testing is imperative to arrive at the proper diagnosis and to initiate appropriate local and systemic treatment. Positive antineutrophil cytoplasmic antibody (ANCA) test results may be found in an unexpectedly large proportion of patients with CIMDL. In several instances their lesions are clinically indistinguishable from granulomatosis with polyangiitis (Wegener's) limited to the upper respiratory tract. CIMDL seem to be the result of a necrotizing inflammatory tissue response triggered by cocaine abuse in a subset of patients predisposed to produce ANCA, particularly those reacting with HNE. The presence of these HNE-ANCA seems to promote or define the disease phenotype. CIMDL do not respond well to immunosuppressive therapy. Only the consistent removal of persistent stimuli of autoantibody production (cocaine, bacterial superinfections) can halt the disease process, prevent the progression of the lesions and promise success of surgical repair procedures.

Drug development of intranasally delivered peptides

Intranasal drug delivery has attracted increasing attention as a noninvasive route of administration for therapeutic proteins and peptides. The delivery of therapeutic peptides through the nasal route provides an alternative to intravenous or subcutaneous injections. This review highlights the drug-development considerations unique to nasal therapeutics and discusses some of the factors and strategies that affect and can improve nasal absorption of peptides. The selectivity and good safety profile typical of peptide therapeutics, along with the dose limitation for intranasal administration, can provide challenges in drug development. Therefore, nasal peptide therapeutics often require special considerations in the nonclinical safety evaluations, such as determining drug exposure in the context of the maximum feasible dose in order to adequately prepare nasal products for clinical studies.

Trouble with bleeding: risk factors for acute hepatitis C among HIV-positive gay men from Germany--a case-control study

OBJECTIVES

To identify risk factors for hepatitis C among HIV-positive men who have sex with men (MSM), focusing on potential sexual, nosocomial, and other non-sexual determinants.

BACKGROUND

Outbreaks of hepatitis C virus (HCV) infections among HIV-positive MSM have been reported by clinicians in post-industrialized countries since 2000. The sexual acquisition of HCV by gay men who are HIV positive is not, however, fully understood.

METHODS

Between 2006 and 2008, a case-control study was embedded into a behavioural survey of MSM in Germany. Cases were HIV-positive and acutely HCV-co-infected, with no history of injection drug use. HIV-positive MSM without known HCV infection, matched for age group, served as controls. The HCV-serostatus of controls was assessed by serological testing of dried blood specimens. Univariable and multivariable regression analyses were used to identify factors independently associated with HCV-co-infection.

RESULTS

34 cases and 67 controls were included. Sex-associated rectal bleeding, receptive fisting and snorting cocaine/amphetamines, combined with group sex, were independently associated with case status. Among cases, surgical interventions overlapped with sex-associated rectal bleeding.

CONCLUSIONS

Sexual practices leading to rectal bleeding, and snorting drugs in settings of increased HCV-prevalence are risk factors for acute hepatitis C. We suggest that sharing snorting equipment as well as sharing sexual partners might be modes of sexual transmission. Condoms and gloves may not provide adequate protection if they are contaminated with blood. Public health interventions for HIV-positive gay men should address the role of blood in sexual risk behaviour. Further research is needed into the interplay of proctosurgery and sex-associated rectal bleeding.

Cocaine-induced midline destructive lesions mimicking ENT-limited Wegener's granulomatosis

The prevalence of cocaine use is rising worldwide, with a resultant rise in associated pathology. Regular nasal use can cause cocaine-induced midline destructive lesions (CIMDL), which can be difficult to distinguish from ear, nose, and throat (ENT)-limited Wegener's granulomatosis (WG). Two cocaine users presented with mid-facial pain, epistaxis, and systemic symptoms. Both had nasal septal perforation, necrosis of sinus mucosa, and positive anti-neutrophil cytoplasmic antibodies (ANCA). Histology was inconclusive and treatment with immunosuppressive drugs was commenced. The first patient continued to use cocaine initially, with improvement in her symptoms only on high doses of steroid. Later she stopped cocaine and this plus a switch from cyclophosphamide to mycophenolate mofetil resulted in successful symptom resolution and steroid withdrawal. The second patient denied cocaine use but having only partially responded to high-dose prednisolone and methotrexate, she admitted continued cocaine use and was lost to follow-up. Evaluation of a patient with destructive lesions of the mid-face should include enquiry about intranasal use of cocaine. Localized ENT involvement, inconsistent ANCA pattern, and atypical biopsy findings for WG should be recognized as features of CIMDL. Although cessation of cocaine use is crucial, there may be a role for immunosuppression.

Functional characterization of antineutrophil cytoplasmic antibodies in patients with cocaine-induced midline destructive lesions

OBJECTIVE

Antineutrophil cytoplasmic antibodies (ANCA) binding to neutrophil elastase (NE) and proteinase 3 (PR3) are detectable in most patients with cocaine-induced midline destructive lesions (CIMDL), but the pathogenic role and antigen specificity of these antibodies are unknown. This study was undertaken to assess the effects of NE ANCA on the enzymatic activity of NE, to determine whether these antibodies interfere with the physiologic effect of secretory leukoprotease inhibitor (SLPI), and to investigate the antigen specificity of both NE and PR3 ANCA in patients with CIMDL. We also compared the binding of PR3 ANCA in patients with CIMDL with that in patients with Wegener's granulomatosis (WG).

METHODS

PR3 ANCA and NE ANCA were detected by capture enzyme-linked immunosorbent assays (ELISAs) and by indirect immunofluorescence. IgG was purified from the patients' sera, and the influence of NE ANCA on the enzymatic activity of NE and on the inhibitory activity of SLPI was investigated by determining the hydrolysis of N-methoxysuccinyl-Ala-Ala-Pro-Val p-nitroanilide by NE.

RESULTS

IgG from NE ANCA-positive sera of patients with CIMDL inhibited the enzymatic activity of NE and did not interfere with the activity of SLPI. In contrast to the findings in WG sera, measurement of PR3 ANCA in CIMDL sera showed only fair to moderate concordance between the 2 different capture ELISAs. Cross-inhibition experiments demonstrated that NE ANCA and PR3 ANCA represent distinct autoantibodies in patients with CIMDL.

CONCLUSION

The functional effects of NE ANCA on the enzymatic activity of NE or on the activity of SLPI cannot be implicated in the pathogenesis of CIMDL. The autoimmune reaction that targets neutrophil serine proteases in patients with CIMDL is frequently directed against more than one antigen. The ANCA response, including the reactivity of PR3 ANCA, in patients with CIMDL differs from what has been described in patients with WG.

Characterization of cocaine-elicited cell vacuolation: the involvement of calcium/calmodulin in organelle deregulation

The sizes of organelles are tightly regulated in the cells. However, little is known on how cells maintain the homeostasis of these intracellular compartments. Using cocaine as a model compound, we have characterized the mechanism of deregulated vacuolation in cultured rat liver epithelial Clone 9 cells. The vacuoles were observed as early as 10 min following cocaine treatment. Removal of cocaine led to vacuole degeneration, indicating vacuolation is a reversible process. The vacuoles could devour intracellular materials and the vacuoles originated from late endosome/lysosome as indicated by immunofluorescence studies. Instant calcium influx and calmodulin were required for the initiation of vacuole formation. The unique properties of these late endosome/lysosome-derived vacuoles were further discussed. In summary, cocaine elicited a new type of deregulated vacuole and the involvement of calcium/calmodulin in vacuolation could shed light on prevention or treatment of cocaine-induced cytotoxicity.