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Dive into the research topics where Michael Gaisa is active.

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Featured researches published by Michael Gaisa.


AIDS | 2014

High rates of anal dysplasia in HIV-infected men who have sex with men, women, and heterosexual men.

Michael Gaisa; Keith Sigel; Jonathan Hand; Stephen E. Goldstone

Objective:To determine rates of anal dysplasia in a cohort of HIV-infected men who have sex with men (MSM), women, and heterosexual men with abnormal anal cytology. Design/methods:We evaluated histologic findings in 728 HIV-infected MSM, women, and heterosexual men referred for high-resolution anoscopy (HRA) after abnormal anal cytology in a single-center cohort study. Using multivariable logistic regression, we evaluated predictors of high-grade squamous intraepithelial lesion (HSIL) histology or invasive carcinoma including age, sexual behavior, receptive anal intercourse (RAI), anogenital warts, smoking status, antiretroviral therapy, CD4+ T-cell count, and HIV-1 plasma viral load. Results:A total of 2075 HIV-positive patients were screened with anal cytology and 62% of MSM, 42% of women, and 29% of heterosexual men had abnormal findings (P <0.001). Of the 728 HIV-infected patients with abnormal anal cytology who underwent HRA, 71% were MSM, 23% women, and 6% heterosexual men. HSIL/cancer was found in 32% of MSM, 26% of women, and 23% of heterosexual men (P = 0.3). There were five cases of anal squamous cell carcinoma (0.7%), four in MSM and one in a heterosexual man. In a multivariable adjusted analysis, biopsy-proven HSIL/cancer was associated with RAI [odds ratio (OR) 2.2; 95% confidence interval (CI) 1.3–3.7]. CD4+ T-cell counts more than 500/&mgr;l conferred a lower risk of HSIL/cancer (OR 0.5; 95% CI 0.3–0.9). Conclusion:Rates of anal HSIL histology are high in HIV-infected patients of all sexual risk groups with abnormal anal cytology. Consequently, all HIV-infected patients may warrant anal cancer screening.


Journal of Acquired Immune Deficiency Syndromes | 2014

Random Biopsy During High-Resolution Anoscopy Increases Diagnosis of Anal High-Grade Squamous Intraepithelial Lesions

Richard Silvera; Michael Gaisa; Stephen E. Goldstone

Objective:Random biopsy (RB) of normal appearing cervix during colposcopy increases high-grade dysplasia (HSIL) diagnosis but has not been studied in high-resolution anoscopy (HRA), that is, colposcopy transferred to the anal canal. We investigated the utility of RB during HRA. Design:At HRA, the anal canal was divided into 4 quadrants. Areas suspicious for HSIL had standard biopsy (SB); random biopsies were taken from quadrants without apparent HSIL. Inclusion required ≥1 RB. Two providers performed all procedures (S.E.G., >10 years experience; M.M.G. 3 years experience)[LINE SEPARATOR] Results:Overall, 391 participants enrolled (mean age, 44.7 years); most were male (87.2%), non-Hispanic (69.8%), white (62.7%), and HIV positive (72.9%). Of 1761 biopsies, 883 were RBs (mean, 2.26/participant). HSIL was identified in 252 lesions, and in 132 participants (33.8%). Thirty-two HSILs (12.7%) and 13 participants (9.8%) were diagnosed by RB. RB increased total HSILs identified per participant (mean, 0.65 vs. 0.56; P < 0.001) and participants with HSIL (P < 0.001). Histologically, HSIL diagnoses via SB were no more dysplastic than random biopsies (relative risk, 0.82; range, 0.37–1.8). In multivariable analysis, factors affecting adjusted relative risk (ARR) of HSIL with any biopsy were provider [S.E.G vs. M.M.G.; ARR, 5.9; 95% confidence interval (CI), 1.3 to 25.8] and oncogenic human papillomaviral infection (ARR, 24.3; 95% CI, 2.8 to 213.3). Risk of HSIL on RB alone in multivariate analysis was associated with HSIL via SB (ARR, 3.4; 95% CI, 1.6 to 7.1 or ARR, 1.4; 95% CI, 1.1 to 1.9 per standard HSIL). Provider, HIV status, detectable viral load, age, or prior screening for or treatment of HSIL did not affect the utility of RB. Conclusions:Addition of RB to HRA significantly increased both the number of HSILs and participants with HSIL identified.


Clinical Infectious Diseases | 2017

High Rates of Anal High-Grade Squamous Intraepithelial Lesions in HIV-Infected Women Who Do Not Meet Screening Guidelines

Michael Gaisa; Fanny Ita-Nagy; Keith Sigel; Yotam Arens; Mary Ann Hennessy; Gabriela Rodriguez-Caprio; Michael P. Mullen; Judith A. Aberg; Michelle Cespedes

Background. Human immunodeficiency virus (HIV)–infected women have a higher burden of anal high-grade squamous intraepithelial lesions (HSIL) and anal cancer (AC) compared with HIV-uninfected women. Guidelines for AC screening in this population are heterogeneous. Here we report outcomes and risk factors for anal HSIL following implementation of universal AC screening offered to all HIV-infected women. Methods. Data from women who underwent AC screening with anal cytology from April 2009 to July 2014 were analyzed. Routine clinical data included anal and cervical cytology, demographic/behavioral data, and high-resolution anoscopy (HRA) results. We evaluated the association of cytology with HRA results, and predictors of HSIL pathology, and compared rates of HSIL pathology among women meeting screening guidelines to those who did not. Results. Seven hundred forty-five HIV-infected women were screened with anal cytology. Thirty-nine percent had abnormal anal cytology on initial screen and 15% on secondary screen; 208 women underwent HRA following abnormal anal cytology. HSIL was found in 26% and 18% of anal biopsies following initial and secondary screening, respectively. One woman had AC. Cigarette smoking more than doubled HSIL risk. Among women who underwent AC screening despite not meeting existing guideline criteria, 21% and 10%, respectively, were found to have HSIL on biopsy. Neither meeting criteria for screening nor history of receptive anal sex was significantly associated with HSIL. Conclusions. Anal HSIL is common in HIV-infected women. Substantial numbers of HSIL would have been missed by strictly adhering to existing AC screening guidelines. These results support routine screening of all HIV-infected women regardless of human papillomavirus history or sexual practices.


Clinical Infectious Diseases | 2017

Shedding of Hepatitis C Virus Into the Rectum of HIV-infected Men Who Have Sex With Men.

Andrew L. Foster; Michael Gaisa; Rosanne M. Hijdra; Samuel S. Turner; Tristan Morey; Karen B. Jacobson; Daniel S. Fierer

Background. For over a decade we have known of an epidemic of sexually transmitted hepatitis C virus (HCV) infection among human immunodeficiency virus (HIV)-infected men who have sex with men (MSM), but there still remains significant controversy over which bodily fluid(s) are responsible for HCV transmission in these men. Methods. We enrolled HIV-infected MSM with recent and chronic HCV infection and quantified HCV from rectal fluid obtained by blind swab. We compared the rectal HCV viral load (VL) with paired blood HCV VL. Results. We found rectal HCV shedding in 20 (47%) of 43 men, only one (2%) of whom had visible bleeding. Detection of rectal HCV shedding was associated with blood VL > 5 log10 IU/mL (p = .01), and 85% with blood VL > 5 log10 IU/mL had rectal shedding. The HCV VL of the rectal fluid ranged from 2.6 to 5.5 log10 IU/mL. Based on the median rectal fluid VL, the surface of an average human penis would be exposed to at least 2,300 IU of HCV for the duration of anal intercourse. Conclusion. This study provides the first direct evidence to our knowledge that a sufficient quantity of HCV is shed into the rectum in HIV-infected men with HCV infection to directly infect an inserted penis or be passed indirectly through fomite-like transmission to the rectum of sex partner. We must develop an appropriate public health campaign to educate MSM about these routes of HCV infection to reverse the HCV epidemic among HIV-infected MSM.


American Journal of Clinical Pathology | 2017

Anal High-Grade Squamous Intraepithelial Lesions in Human Immunodeficiency Virus–Infected Men

Yuxin Liu; Xiaofei Wang; Tamara Kalir; David Chhieng; Keith Sigel; Michael Gaisa

Objectives Anorectal cytology (ARC) is a widely used screening tool for anal cancer in human immunodeficiency virus (HIV)-infected men who have sex with men (MSM). Its diagnostic accuracy needs to be improved, especially for high-grade squamous intraepithelial lesions (HSILs). Methods Using 100 HIV+ MSM with biopsy-proven anal HSILs, we correlated histologic/cytologic findings. Results Upon review, HSIL cells were present in 58 cytology samples and absent in 42. Positive samples were higher in cellularity and contained transformation zones ( P  < .05). Cytology was able to predict HSILs in 36%, 48%, 68%, and 78% of patients with one, two, three, and four or more high-grade lesions. HSIL cells were identified in all cytology samples initially reported as HSILs or atypical squamous cells, cannot exclude HSIL and in 34 samples reported as low-grade squamous intraepithelial lesions or less. Notably, among this last category, 15 (44%) were keratinized-type HSILs. Conclusions Our findings should improve the ARC detection rate for anal HSILs, helping to implement ARC as the primary screening tool for anal cancer.


Sexually Transmitted Diseases | 2017

Prevalence of Anal Dysplasia in Human Immunodeficiency Virus–Infected Transgender Women

Takaaki Kobayashi; Keith Sigel; Michael Gaisa

Abstract Although human immunodeficiency virus–infected men who have sex with men are at high risk for anal cancer, little is known about the prevalence of anal dysplasia in human immunodeficiency virus (HIV)-infected transgender women. Our study found that prevalence rates of abnormal anal cytology and histology in HIV-infected transgender women were similar to those in HIV-infected men who have sex with men.


The Journal of Infectious Diseases | 2018

Human Papillomavirus Genotypes Predict Progression of Anal Low-Grade Squamous Intraepithelial Lesions

Yuxin Liu; Keith Sigel; Michael Gaisa

Background High-risk human papillomavirus (hrHPV)-induced anal low-grade squamous intraepithelial lesions (LSILs) have the potential to progress to high-grade squamous intraepithelial lesions (HSILs). We investigated whether anal hrHPV infections, particularly types 16 and 18, predict LSIL-to-HSIL progression. Methods One hundred forty-six human immunodeficiency virus (HIV)-infected and 22 HIV-uninfected patients with anal LSILs underwent cytology, HPV genotyping (16, 18, and pooled 12 hrHPV types), and high-resolution anoscopy-guided biopsy at baseline and surveillance. The associations between the rate of LSIL-to-HSIL progression and HPV types as well as longitudinal HPV-16/18 status were assessed by fitting separate Cox regression models. Results At baseline, 91% of patients harbored hrHPV: HPV-16/18 (44%) and non-16/18 (86%). Upon follow-up (median, 20 [range, 6-36] months), 41% developed HSIL (84% at the same anatomic location as the initial LSIL and 16% at a different location). Baseline HPV-16/18-positive patients had greater probability of progression than patients with non-16/18 types or negative (67%, 25%, and 7%, respectively; P < .001). Persistent HPV-16/18 conferred the highest probability of progression (70%), followed by intermittent HPV-16/18 positivity (52%). In unadjusted and adjusted analyses, baseline and persistent HPV-16/18 were significantly associated with LSIL-to-HSIL progression. Conclusions Anal LSIL patients who are positive for hrHPV, especially HPV-16/18, have an increased risk of developing HSIL. Type-specific HPV testing could serve as a risk stratification tool, providing prognostic information.


The Journal of Infectious Diseases | 2018

Differences in the Immune Microenvironment of Anal Cancer Precursors by HIV Status and Association With Ablation Outcomes

Yuxin Liu; Michael Gaisa; Xiaofei Wang; Talia H. Swartz; Yotam Arens; Karen Dresser; Carlie Sigel; Keith Sigel

Background Anal high-grade squamous intraepithelial lesions (HSILs) are the precursors to anal cancer and frequently persist or recur following electrocautery ablation (EA). Impaired mucosal immunity may facilitate anal carcinogenesis. We characterized the immune microenvironment of anal HSILs in correlation with human immunodeficiency virus (HIV) serostatus and ablation outcomes. Methods Using immunohistochemistry, mucosa-infiltrating CD4+ and CD8+ lymphocytes were quantified in HSILs and benign mucosa from 70 HIV+ and 45 HIV- patients. Clinicopathological parameters were compared. Results Anal HSILs harbored more T lymphocytes than benign mucosa regardless of HIV status (P ≤ .03). Total T lymphocyte count and CD8+ subset were significantly higher in HIV+ HSILs versus HIV- HSILs (median cell count, 71 vs 47; 47 vs 22/high power field [HPF]; P < .001), whereas the CD4+ subset was comparable between groups (median, 24 vs. 25; P = .40). Post EA, HSILs persisted in 41% of HIV+ and 19% of HIV- patients (P = .04). Unadjusted analysis showed trends toward EA failures associated with HIV seropositivity (incidence rate ratio [IRR], 2.0; 95% CI, .8-4.9) and increased CD8+ cells (IRR, 2.3; 95% CI, .9-5.3). Conclusions Human immunodeficiency virus is associated with alterations of the immune microenvironment of anal HSILs manifested by increased local lymphocytic infiltrates, predominately CD8+. Human immunodeficiency virus seropositivity and excess mucosa-infiltrating CD8+ cells may be associated with ablation resistance.


Open Forum Infectious Diseases | 2018

Ledipasvir and Sofosbuvir in the Treatment of Early Hepatitis C Virus Infection in HIV-Infected Men

Paari M Palaniswami; Ahmed El Sayed; Benjamin Asriel; Jesse R Carollo; Daniel S. Fierer; Bisher Akil; Paul Bellman; Daniel Bowers; Krisczar Bungay; Susanne Burger; Aviva Cantor; Rachel Chasan; Robert Chavez; Rita Chow; Robert M. Cohen; Patrick Dalton; John Dellosso; Stephen M. Dillon; Eileen Donlon; Terry Farrow; Jose Fefer; Michael Gaisa; Rodolfo Guadron; Stuart Haber; Susan Hefron; Lawrence Higgins; Lawrence Hitzeman; Ricky Hsu; Shirish Huprikar; Victor Inada

Abstract Background Treatment of HIV-infected men during early hepatitis C virus (HCV) infection with interferon results in a higher cure rate with a shorter duration of treatment than during chronic HCV infection. We recently demonstrated that this phenomenon applied to interferon-free treatment as well, curing most participants with short-course sofosbuvir and ribavirin. Due to the significantly higher potency of the ledipasvir/sofosbuvir (LDV/SOF) combination, we hypothesized that we would be more successful in curing early HCV infections using a shorter course of LDV/SOF than that used for treating chronic HCV infections. Methods We performed a prospective, open-label, consecutive case series study of 8 weeks of LDV/SOF in HIV-infected men with early genotype 1 HCV infection. The primary end point was aviremia at least 12 weeks after completion of treatment. Results We treated 25 HIV-infected men with early sexually acquired HCV infection with 8 weeks of LDV/SOF, and all 25 (100%) were cured. Twelve (48%) reported sexualized drug use with methamphetamine. Conclusions Eight weeks of LDV/SOF cured all 25 HIV-infected men with early HCV infection, including those who were actively using drugs. Based on these results, we recommend treatment of newly HCV-infected men during early infection, regardless of drug use, to both take advantage of this 8-week treatment and to decrease further HCV transmission among this group of men.


AIDS | 2010

Successful initiation of an anal cancer screening and treatment program at a New York City Hiv clinic

Diane S Tider; Gabriela Rodriguez Caprio; Michael Gaisa; Robert S. Klein; Stephen E. Goldstone

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Keith Sigel

Icahn School of Medicine at Mount Sinai

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Yuxin Liu

Icahn School of Medicine at Mount Sinai

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Stephen E. Goldstone

Icahn School of Medicine at Mount Sinai

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Yotam Arens

Icahn School of Medicine at Mount Sinai

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Daniel S. Fierer

Icahn School of Medicine at Mount Sinai

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David Chhieng

Icahn School of Medicine at Mount Sinai

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Karen B. Jacobson

Icahn School of Medicine at Mount Sinai

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Andrew L. Foster

Icahn School of Medicine at Mount Sinai

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Dan Lu

Icahn School of Medicine at Mount Sinai

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Judith A. Aberg

Icahn School of Medicine at Mount Sinai

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