Broad Antimicrobial Resistance in a Case of Relapsing Babesiosis Successfully Treated With Tafenoquine

We describe a case of relapsing babesiosis in an immunocompromised patient. A point mutation in the Babesia microti 23S rRNA gene predicted resistance to azithromycin and clindamycin, whereas an amino acid change in the parasite cytochrome b predicted resistance to atovaquone. Following initiation of tafenoquine, symptoms and parasitemia resolved.

Tecovirimat for the treatment of human monkeypox: an initial series from Massachusetts, United States

A large, ongoing multicountry outbreak of human monkeypox has the potential to cause considerable morbidity and mortality. Therapeutics for the treatment of smallpox, a related Orthopoxvirus, may be used and affect the natural history of monkeypox. We present 3 patients from our hospitals treated with tecovirimat, a pan-Orthopoxvirus inhibitor currently available under an expanded access investigational new drug protocol for monkeypox.

Sustained HIV Viral Suppression With Dolutegravir, Tenofovir, and Emtricitabine as Initial Therapy Despite High-Level Transmitted Multiclass Resistance

Multiclass high-level transmitted HIV drug resistance is uncommon, and the selection of the optimal initial antiretroviral drug regimen may be challenging. We report a case of extensive transmitted multiclass resistance successfully treated with dolutegravir, tenofovir, and emtricitabine even though the baseline genotype demonstrated full susceptibility to only 1 drug class, integrase strand transfer inhibitors. Our case highlights both the high resistance barrier of dolutegravir and the residual antiviral activity of nucleoside reverse transcriptase inhibitors despite extensive resistance on genotype.

Underascertainment of acute hepatitis C virus infections in the U.S. surveillance system: a case series and chart review

BACKGROUND

In 2010, the incidence of hepatitis C virus (HCV) infection in the United States was estimated to be 17 000 cases annually, based on 850 acute HCV cases reported to the Centers for Disease Control and Prevention by local public health authorities. Absence of symptomatic disease and lack of a specific laboratory test for acute infection complicates diagnosis and surveillance.

OBJECTIVE

To validate estimates of the incidence of acute HCV infection by determining the reporting rate of clinical diagnoses of acute infection to the Massachusetts Department of Public Health (MDPH) and Centers for Disease Control and Prevention.

DESIGN

Case series and chart review.

SETTING

Two hospitals and the state correctional health care system in Massachusetts.

PATIENTS

183 patients clinically diagnosed with acute HCV infection from 2001 to 2011 and participating in a research study.

MEASUREMENTS

Rate of electronic case reporting of acute HCV infection to the MDPH and rate of subsequent confirmation according to national case definitions.

RESULTS

149 of 183 (81.4%) clinical cases of acute HCV infection were reported to the MDPH for surveillance classification. The MDPH investigated 43 of these reports as potential acute cases of HCV infection based on their surveillance requirements; ultimately, only 1 met the national case definition and was counted in nationwide statistics published by the Centers for Disease Control and Prevention. Discordance in clinical and surveillance classification was often related to missing clinical or laboratory data at the MDPH as well as restrictive definitions, including requirements for negative hepatitis A and B laboratory results.

LIMITATION

Findings may not apply to other jurisdictions because of differences in resources for surveillance.

CONCLUSION

Clinical diagnoses of acute HCV infection were grossly underascertained by formal surveillance reporting. Incomplete clinician reporting, problematic case definitions, limitations of diagnostic testing, and imperfect data capture remain major limitations to accurate case ascertainment despite automated electronic laboratory reporting. These findings may have implications for national estimates of the incidence of HCV infection.

PRIMARY FUNDING SOURCE

National Institutes of Health.

A simple strategy to identify acute hepatitis C virus infection among newly incarcerated injection drug users

Acute hepatitis C virus (HCV) infection is underdiagnosed because most patients are asymptomatic. The majority of new infections occur among people who inject drugs (PWID), many of whom have a history of incarceration. In a previous pilot study, we identified symptomatic HCV cases, mainly among Caucasian inmates. We designed a cross-sectional study to evaluate whether risk factor-based screening of newly incarcerated inmates would enhance identification of asymptomatic acute HCV infection and elucidate any demographic shifts in HCV acquisition. From October 2006 to March 2008, 6,342 inmates underwent health assessments and 3,470 inmates (55%) were screened. The racial distribution was as follows: African American, 24.0%; Caucasian, 49.5%; Hispanic, 22.2%. One hundred seventy-one inmates (4.9%) were classified as high-risk. After further evaluation, 35 (20.5%) inmates were diagnosed with acute HCV with a mean age of 29 years; 62.9% were female and 91% were Caucasian. No African Americans were diagnosed with acute HCV. Our case-finding rate was 1.9 patients/month nearly a three-fold increase compared with our historical control period with a higher proportion of asymptomatic cases. We estimate a prevalence of ∼1.0% (95% confidence interval, 0.7%-1.4%) of acute HCV infections among newly incarcerated inmates.

CONCLUSION

Within the correctional system, systematic screening based on risk factors successfully identifies acute HCV infection among PWID, including asymptomatic patients. Our data also reflect changing nationwide patterns of injection drug use that vary by age, ethnicity, and race, leading to a marked reduction of acute HCV infections among African Americans compared with non-Hispanic whites. The nationwide implementation of this simple low-cost strategy in prison-based settings could identify more than 7,000 acute HCV infections among PWID, provide insight into changing epidemiologic trends, and facilitate appropriate therapeutic and preventive interventions.

Clinical predictors for the aetiology of peripheral lymphadenopathy in HIV-infected adults

OBJECTIVES

The aim of the study was to determine the aetiology and clinical predictors of peripheral lymphadenopathy in HIV-infected individuals during the antiretroviral (ARV) era in a nontuberculosis endemic setting.

METHODS

A multicentred, retrospective cohort study of peripheral lymph node biopsies in HIV-positive adults was carried out. A total of 107 charts were identified and reviewed for clinical features, lymphadenopathy size, and ARV use and duration. Biopsy results were categorized, and multivariate logistic regression determined independent predictors of lymphadenopathy aetiology.

RESULTS

Evaluation of 107 peripheral lymph node biopsies revealed that 42.9% of peripheral lymphadenopathy was attributable to malignancy, 49.5% to reactive changes, and 7.5% to infections, with only 2.8% of all cases secondary to tuberculosis. Fevers, weight loss, ARV use, and lower viral loads are significantly associated with nonreactive lymphadenopathy.

CONCLUSIONS

Lymphadenopathy is likely to be reactive or malignant in nontuberculosis endemic regions. Readily available clinical features can aid clinicians in predicting the underlying aetiology, those at risk for malignancy, and who to biopsy.

A "one-two punch" leading to hepatitis C seroconversion

We report a case of acute hepatitis C virus infection that occurred after a traumatic altercation among prison inmates. This report has significant implications for infection control policies and procedures in prisons and jails, where the estimated prevalence of hepatitis C virus infection is ∼20 times that of the general population.

The major genetic determinants of HIV-1 control affect HLA class I peptide presentation

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.

Rate of sustained virologic response in relation to baseline hepatitis C virus (HCV) RNA level and rapid virologic clearance in persons with acute HCV infection

Treatment of acute hepatitis C virus (HCV) infection leads to a sustained virologic response (SVR) in the vast majority of patients, although the clinical predictors of these favorable responses are not well understood. In chronic infection, the most potent predictor of a SVR is complete viral suppression after 4 weeks of treatment, also known as a rapid virologic response (RVR). However, few patients with HCV genotype 1 infection and high-level viremia ever achieve this benchmark. In 2 separate cohorts of patients with acute HCV infection, we demonstrate that rapid virologic clearance and low-level viremia (HCV RNA level, <400,000 IU/mL) are highly prevalent, regardless of HCV genotype.

Improving the diagnosis of acute hepatitis C virus infection with expanded viral load criteria

BACKGROUND

The diagnosis of acute hepatitis C virus (HCV) infection is imprecise because antibody testing does not differentiate between acute and chronic infection. Although virologic features, such as viral load fluctuations and low levels of viremia, have been noted to be characteristic of acute HCV infection, these parameters have not been used for diagnosis.

METHODS

We validated the use of these novel parameters (ie, viral load fluctuations >1 log and HCV RNA levels <100,000 IU/mL) in a cohort of acute HCV seroconverters. We then applied standard diagnostic criteria for acute HCV infection in a cohort of high-risk injection drug users entering prison with suspected acute HCV infection (n=37). We subsequently assessed whether these novel virologic parameters, measured serially over a 10-week period, could enhance the diagnosis of acute infection.

RESULTS

Low-level viremia and viral load fluctuations were highly prevalent in our cohort of acute seroconverters (81% and 86%, respectively), whereas low-level viremia occurred in only 13% of control patients with chronic infection. With use of standard criteria, 37 inmates received a diagnosis of acute HCV infection. Among the 35 patients with HCV RNA detectable at baseline, we found low-level viremia to be highly prevalent (n=27; 77%); among patients with a minimum of 2 HCV RNA samples, we demonstrated viral fluctuations in more than one-third (n=9; 36%).

CONCLUSIONS

The diagnosis of acute infection in HCV-seropositive patients is strengthened by the use of virologic parameters that are uncommon in chronic disease. Viral load fluctuations and low levels of HCV RNA should be incorporated into standard diagnostic criteria.