Alice C. Thornton

Levofloxacin Failure in a Patient with Pneumococcal Pneumonia

OBJECTIVE: To report a case of levofloxacin failure in a patient with a penicillin-sensitive Streptococcus pneumoniae pneumonia. CASE SUMMARY: A previously healthy, immunocompetent, 53-year-old white man presented with penicillin-sensitive S. pneumoniae pneumonia. The patient was empirically placed on levofloxacin monotherapy, which was continued due to a local penicillin shortage. When the patient failed to improve, further susceptibility testing was ordered. The organism was found to have a penicillin minimum inhibitory concentration (MIC) of 0.023 μg/mL and a levofloxacin MIC of 6 μg/mL. Effective antimicrobial therapy was delayed, as clinicians did not anticipate fluoroquinolone resistance. DISCUSSION: Newer fluoroquinolones such as levofloxacin have good activity against most S. pneumoniae isolates and are used for the treatment of pneumonia. Although resistance to these agents is rare, it has been reported. Current guidelines from the National Committee for Clinical Laboratory Standards do not recommend initial fluoroquinolone susceptibility testing. CONCLUSIONS: As fluoroquinolone resistance may not be identified by susceptibility patterns to other antibiotics, early fluoroquinolone susceptibility testing and increased awareness of resistance may aid clinicians in their treatment of pneumococcal disease.

Poppers: Epidemiology and Clinical Management of Inhaled Nitrite Abuse

Commonly referred to as “poppers,” inhaled nitrites have a long history of abuse. Poppers are rapid‐onset, short‐acting potent vasodilators that produce a rush characterized by warm sensations and feelings of dizziness. Poppers sometimes are used to facilitate anal intercourse because of their actions on the anal sphincter. Epidemiologically, the frequent use of nitrites by men who have sex with men has led some experts to implicate these chemicals in the pathogenesis of Kaposis sarcoma and acquired immunodeficiency syndrome. Controlled clinical trials to examine this potential correlation have not been conducted, and the use of nitrites simply may be a marker for other high‐risk behaviors such as unprotected sex. Although regulated in the United States, many nitrite compounds and isomers are sold at various venues including bars, bookstores, and over the Internet. Adverse effects associated with these products vary from mild allergic reactions to life‐threatening methemo‐globinemia. The potential for drug‐drug interactions and a propensity toward unsafe sex also exist. Clinicians should be familiar with the populations most likely to abuse these agents and with the clinical effects and management guidelines for acute ingestions.

Impact of Poor Retention in HIV Medical Care on Time to Viral Load Suppression

Objective: The purpose of this study was to evaluate how poor retention in HIV care impacts time to viral suppression after initiating highly active antiretroviral therapy. Methods: A retrospective cohort study design, employing a medical chart review, was conducted at an academic infectious disease clinic at the University of Kentucky. Patients seeking care between 2003 and 2011 were included in the study. A log-normal model was employed to determine the factors associated with time to viral suppression. Results: Of the 532 patients in the study, 426 (80.1%) patients were virally suppressed. Controlling for insurance status, race, baseline CD4 counts, and viral loads, the expected time to viral suppression for nonoptimal retainers was longer compared to optimal retainers (100% retained in care; time ratio: 2.04; 95% confidence interval: 1.40-2.90). Conclusion: Researchers should continue to study the impact of retention on clinical outcomes and strategies to improve retention and reengage those lost to follow-up back into care.

Metronidazole-induced pancreatitis in a patient with recurrent vaginal trichomoniasis.

Recurrent acute pancreatitis associated with metronidazole developed in a 49‐year‐old woman who was taking the drug as treatment for vaginal trichomoniasis. The lack of alternative effective therapies for trichomoniasis governed the decision to rechallenge the patient with metronidazole despite a vague history of this reaction on a previous occasion. Six reports of this reaction are found in the literature. The patient was admitted to the hospital 12 hours after taking a single dose of metronidazole. Severe epigastric pain and elevated amylase and lipase concentrations led to the diagnosis of acute pancreatitis, although results of an abdominal ultrasound were unremarkable. The patient made a full recovery. Although this reaction occurs infrequently, this case report illustrates the need to develop additional therapies for treatment of trichomoniasis.

Tenofovir-associated severe bone pain: I cannot walk!

Two adult patients living with AIDS presented with severe bone pain associated with tenofovir (TDF) use. Both were unable to walk without assistance and were severely restricted in their movement due to the bone pain. Both had mild renal impairment, Fanconi syndrome, and bone mineral density (BMD) loss. Bone pain and inability to walk were reversible with the cessation of TDF and supplementation with Vitamin D3, calcium, and phosphate. These cases appear to be examples of the severity of BMD loss associated with TDF use and suggest not only attention to renal function with TDF use, but also monitoring of alkaline phosphatase (bone fraction) and plasma phosphorus as indicators of BMD loss.

Role of CD4 Count in Immunity Development After Hepatitis A and B Vaccination Among HIV-Infected Patients: Kentucky, 2002-2007:

Purpose: To determine whether lower prevaccination CD4 counts decrease odds of immune development against hepatitis A virus/hepatitis B virus (HAV/HBV) among patients who receive the vaccine and examine the relationship between vaccine response and sex, race/ethnicity, health insurance status, tobacco use, substance abuse, or comorbidities. Methods: This study was performed among patients who received the standard dose for HAV and/or HBV vaccine. Results: Among 76 HIV-infected patients, immunity development to HAV or HBV increased as CD4 counts increased. In addition, males had greater vaccine response than females. Whites were observed to have higher rates of immunity than other races/ethnicities. Patients with private insurance had greater vaccine response than those with Medicaid, Medicare, or no insurance. Patients not experiencing hypertension and hyperlipidemia developed immunity more often than patients with these comorbidities. Substance abuse and tobacco use were also associated with lower vaccine response. Conclusions: Higher CD4 counts improved likelihood of patients developing an antibody response after vaccination.

Differences in Rhodococcus equi Infections Based on Immune Status and Antibiotic Susceptibility of Clinical Isolates in a Case Series of 12 Patients and Cases in the Literature.

Rhodococcus equi is an unusual zoonotic pathogen that can cause life-threatening diseases in susceptible hosts. Twelve patients with R. equi infection in Kentucky were compared to 137 cases reported in the literature. Although lungs were the primary sites of infection in immunocompromised patients, extrapulmonary involvement only was more common in immunocompetent patients (P < 0.0001). Mortality in R. equi-infected HIV patients was lower in the HAART era (8%) than in pre-HAART era (56%) (P < 0.0001), suggesting that HAART improves prognosis in these patients. Most (85–100%) of clinical isolates were susceptible to vancomycin, clarithromycin, rifampin, aminoglycosides, ciprofloxacin, and imipenem. Interestingly, there was a marked difference in susceptibility of the isolates to cotrimoxazole between Europe (35/76) and the US (15/15) (P < 0.0001). Empiric treatment of R. equi infection should include a combination of two antibiotics, preferably selected from vancomycin, imipenem, clarithromycin/azithromycin, ciprofloxacin, rifampin, or cotrimoxazole. Local antibiograms should be checked prior to using cotrimoxazole due to developing resistance.

Blunted Humoral Response to Influenza Vaccination in Patients Exposed to Zidovudine plus Trimethoprim‐Sulfamethoxazole

Study Objectives. To determine as proof of principle the effect of combination exposure to zidovudine plus trimethoprim‐sulfamethoxazole (TMP‐SMX) on humoral immune responses to influenza vaccination in patients with human immunodeficiency virus (HIV).

Effects of Antiretroviral Therapy on Immunity in Patients Infected with HIV

Drug therapy for human immunodeficiency virus (HIV) is highly effective in suppressing viral replication and restoring immune function in patients with HIV. However, this same treatment can also be associated with immunotoxicity. For example, zidovudine and various other antiretroviral agents are capable of causing bone marrow suppression. Agents used to treat opportunistic infections in these individuals, including ganciclovir, foscarnet, and sulfamethoxazole-trimethoprim, can cause additional hematotoxicity. Drug-drug interactions must also be considered and managed in order to control iatrogenic causes of immunotoxicity. In this review, we examine the normal immune response to HIV, and the benefits of antiretroviral therapy in prolonging immune function. We then discuss immune-related adverse effects of drugs used to treat HIV and the opportunistic infections that are common among these patients. Finally, we address in vitro, animal, and clinical evidence of toxicity associated with various combination use of these agents.

Primary Care Providers’ HIV Prevention Practices Among Older Adults:

Purpose: To explore primary care providers’ HIV prevention practices for older adults. Primary care providers’ perceptions and awareness were explored to understand factors that affect their provision of HIV prevention materials and HIV screening for older adults. Design and Method: Data were collected through 24 semistructured interviews with primary care providers (i.e., physicians, physician assistants, and nurse practitioners) who see patients older than 50 years. Results: Results reveal facilitators and barriers of HIV prevention for older adults among primary care providers and understanding of providers’ HIV prevention practices and behaviors. Individual, patient, institutional, and societal factors influenced HIV prevention practices among participants, for example, provider training and work experience, lack of time, discomfort in discussing HIV/AIDS with older adults, stigma, and ageism were contributing factors. Furthermore, factors specific to primary and secondary HIV prevention were identified, for instance, the presence of sexually transmitted infections influenced providers’ secondary prevention practices. Implications: HIV disease, while preventable, is increasing among older adults. These findings inform future research and interventions aimed at increasing HIV prevention practices in primary care settings for patients older than 50.