Larry M. Bush

Soft Tissue Anaplastic Large T-Cell Lymphoma Associated with a Metallic Orthopedic Implant: Case Report and Review of the Current Literature

On occasion, the placement of orthopedic prosthetic components or stabilization hardware leads to surgical site infections, in some cases presenting at a point in time distant from the surgical procedure. Although infectious complications are the most common etiology for surgical site pain and inflammation, malignancies can also develop around prosthetic devices and metallic implants. When encountered, such malignancies are most often sarcoma, but rarely B-cell non-Hodgkins lymphoma has also been described. In this article, we describe what we believe to be the first published case of anaplastic large T-cell lymphoma associated with a stainless steel fixation plate that was implanted several years earlier for repair of a tibial fracture. Appropriate to this case, we review the medical literature on the association of orthopedic implants with the development of neoplasm, along with the theorized pathogenic mechanisms leading to such an association.

Iatrogenic Cushing Syndrome and Secondary Adrenal Insufficiency Related to Concomitant Triamcinolone and Ritonavir Administration A Case Report and Review

Triamcinolone is a long-acting glucocorticoid medication that can be responsible for transient suppression of the hypothalamic–pituitary–adrenal (HPA) axis. This physiologic alteration may persist for weeks after repeated or even single localized injection of this agent. However, when this glucocorticoid agent is given to patients receiving the HIV protease inhibitor (PI) ritonavir (RTV), inhibition of their shared cytochrome P450 3A4 degradation pathway leads to an increased bioavailability of triamcinolone, with subsequent heightening and prolongation of the glucocorticoid serum levels. In those instances, iatrogenic Cushing syndrome may ensue. The authors encountered such an event in an HIV-infected patient on chronic treatment with an antiretroviral regimen containing RTV. The patient’s clinical presentation and laboratory investigations confirmed a diagnosis of Cushing syndrome and secondary adrenal insufficiency. This was believed to have occurred in close association following cervical vertebral column facet joint injections with triamcinolone acetonide for cephalagia deemed related to cervical spine disease. The discontinuation of the RTV-boosted PI therapy alone, promoting the clearance of the elevated triamcinolone serum levels and restoration of HPA homeostasis, proved successful in this patient. For this case, the authors review the published English medical literature relating to this uncommon phenomenon.

Resistant Herpes Simplex Virus Infection and HIV: A Potential Diagnostic and Therapeutic Dilemma

Herpes simplex virus (HSV) is the most frequent cause of genital ulcer disease worldwide. It is also 1 of the leading infections among HIV-infected individuals. Though HSV-2 is the principal etiologic agent of genital HSV infections (GH), HSV-1 has increasingly become a more common cause of GH, particularly in those with concurrent HIV. The clinical presentation of HSV in HIV-infected patients is often atypical. Individuals with depressed CD4 T-cell lymphocyte counts frequently present with more severe and protracted GH. Extensive, ulcerated, and necrotic lesions may make for a confusing initial clinical diagnosis. Furthermore, treatment with routine anti-herpetic viral agents may result in failure to resolve infection. Motivated by our recent experience involving an AIDS patient with a difficult-to-diagnose genital HSV infection that proved unresponsive to standard treatment, we review the topic of HSV anti-viral medication resistance with particular attention to its association in the HIV/HSV co-infected patient.

Best Alternative to Vancomycin for Serious Methicillin-Resistant Staphylococcus aureus Infections: Let's Just Say It

To the Editor—The recently published articles by Patel et al [1], Kullar et al [2], and Lubin et al [3] persuasively bolster the growing consensus opinion that the goldstandard antimicrobial agent for treatment of serious infections involving methicillinresistant Staphylococcus aureus (MRSA), vancomycin, has become tarnished. Undeniably, these works add to what clearly has become fact: 1) the prevalence of MRSA infections, both inpatient and outpatient, has greatly increased to the point of dominance (inpatient infections); 2) serious infections with MRSA are associated with significantly higher morbidity, mortality, lengths of hospital stay, and total costs, especially when inadequately treated; 3) the rising minimal inhibitory concentration (MIC) of vancomycin against MRSA greatly hinders this drug from achieving the agreed-on required pharmacodynamic parameter (eg, ratio of the area under the concentration–time urve to MIC [AUC/ MIC]

Testing for Tuberculosis: The Roles of Tuberculin Skin Tests and Interferon Gamma Release Assays

400) necessary for adequate bactericidal activity; 4) automated susceptibility testing methods do not accurately reflect the higher MICs produced with standardized methods such as microbroth dilution and E test; and 5) targeting higher serum trough vancomycin levels (15–20 mg/L) to attain an AUC/ MIC

Catheter-associated urinary tract infection IDSA guidelines: why the levofloxacin?

400, as recently recommended in a summary report [4], carries with it a higher probability of drug-induced nephrotoxicity. In light of this information, it is suggested that alternative anti-MRSA agents be considered in treating known or suspected serous MRSA infections, particularly bacteremia. Unfortunately, for the practicing clinician, neither these articles, nor the recently published clinical practice guidelines by the Infectious Diseases Society of America (IDSA) for the treatment of MRSA infections in adults and children [5], offer an opinion as to what actually is, or likely would be, the best alternative anti-MRSA agent. Acknowledging the absence of evidence from any head-to-head clinical trials among the relatively new antimicrobial agents with approved MRSA treatment indications (eg, quinupristin– dalfopristin, linezolid, daptomycin, tigecycline, telavancin, and ceftaroline), the most we may say is that based on the predetermined primary clinical efficacy endpoint of resolution of signs and symptoms, such that no further antimicrobial therapy was required at the testof-cure visit, for the treatment of acute bacterial skin and skin-structure infections (ABSSSI, formerly termed complicated skin and skin-structure infections [cSSSI]) involving Gram-positive microorganisms, including MRSA, each of these agents was noninferior to vancomycin. However, a post hoc analysis of treatment duration among patients achieving clinical success with intravenous therapy alone in the phase 3 trials (cSSSI) involving daptomycin revealed that 63% of patients given daptomycin required only 4–7 days of therapy compared with 33% of patients in the comparator arm that included vancomycin (P , .0001) [6]. Although the 3 days of comparative analysis now required in ABSSSI trials

Ovarian Teratoma-Associated Anti-N-Methyl-D- Aspartate Receptor Autoimmune Encephalitis: A Case Report

The identification of latent tuberculosis infection (LTBI) in any individual or population has proven to carry significant importance not only for that person’s health, but also for the control and eventual elimination of tuberculosis (TB) in the United States. Traditionally, the tuberculin skin test (TST) has served as the standard of care for the identification of prior exposure to Mycobacterium tuberculosis (MTB).nnHowever, the specificity of a positive test is less than optimal. It is either due to previous vaccination intended to prevent TB or infection with nontuberculous mycobacterium (NTM). Newer tests classified as interferon-gamma release assays (IGRA) possess potential advantages over the TST when used for identifying those with MTB infection. We recently diagnosed a case of pleuropulmonary infection involving an unusual NTM, Mycobacterium interjectum (M. interjectum) , in an immunocompromised man diagnosed 1 year after he had been treated for LTBI based on a reactive TST. A propos this experience, we discuss the beneficial role of IGRAs and review the literature on infection with M. interjectum .nn* LTBIn : latent tuberculosis infectionn TSTn : tuberculin skin testn MTBn : Mycobacterium tuberculosisn NTMn : nontuberculous mycobacteriumn IGRAn : interferon gamma release assaysn PPDn : purified protein derivativen BCGn : Bacillus Calmette-Guerinn FDAn : Food and Drug Administrationn IFN-γn : interferon-gamman IGRAsn : interferon-gamma release assaysn INHn : isoniazidn TNF-αn : tumor necrosis factor alphan CXRn : chest radiographn CTn : computerized tomographicn AFBn : acid-fast bacillin TBn : tuberculosisn RAn : rheumatoid arthritisn MTXn : methotrexaten DMARDsn : disease-modifying antirheumatic drugsn CDCn : Centers for Disease Control and Preventionn DTHn : delayed-type hypersensitivityn QFTn : QuantiFERON-TBn QFT-Gn : QuantiFERON-TB Goldn QFT-GITn : QuantiFERON-TB Gold In-Tuben ELISAn : enzyme-linked immunosorbent assayn ESAT-6n : early secretory antigenic target-6n CFP-10n : culture filtrate protein-10n ELISpotn : enzyme-linked immunospot assayn PBMCsn : peripheral blood mononuclear cellsn MOTTn : mycobacteria other than tuberculosis

Rhodococcus equi brain infection in an immunocompetent patient: A case report and review of the literature

cant role. Nevertheless, there were several areas in Dr Aggarwal’s letter that we wish to clarify. First, we believe that, in this epidemic, which continued over many incubation periods, there must have been either a continuing common source or person-toperson transmission. During the period of this investigation, there were several prevention and control measures implemented to ensure safe drinking water and hygienic practices. In addition to hepatitis E virus testing of water sources, testing for coliforms was conducted. Although we agree with Dr Aggarwal regarding the low sensitivity of hepatitis E virus detection techniques from water sources, the absence of hepatitis E virus RNA and significant coliforms from protected water sources argues against any fecal contamination that would contribute to an ongoing common source. Given that there was no evidence of any contamination of these sources while hand lavage yielded hepatitis E virus [2], we believe that person-to-person transmission likely played a significant role. Second, we believe that the assumption of secondary cases representing person-toperson transmission is conservative in that this route could also have contributed to transmission among primary cases. Unlike in Asia, where there may be a higher prevalence of immunity to hepatitis E virus, we believe that a significant proportion of the population was susceptible to hepatitis E virus prior to the widespread outbreak. In our population, this could have contributed to the secondary attack rate, which was much higher than those reported in most studies [3], which were conducted in populations with higher preexisting immunity to hepatitis E virus and where person-to-person transmission was considered insignificant. If there had been a continually contaminated common water source, then we would have expected an even higher attack rate and a shorter outbreak. Regarding Dr Aggarwal’s concern about the range of time periods between primary and secondary cases (ie, 8– 20 weeks), we believe that infection could have been propagated by infected but asymptomatic family members. Another issue regarding household transmission that was raised by Dr Aggarwal deserves comment. In many settings, we would agree with him that household size is associated with socioeconomic status and standard of living. However, in the setting of this outbreak, the socioeconomic status of all residents was uniformly poor, and there was no substantial variation in the living conditions. Although we cannot exclude the possibility that a proportion of secondary cases may have acquired infection from an unidentified common source, we still believe that significant hepatitis E virus personto-person transmission occurred during this large epidemic in northern Uganda.

Tick borne illness—Lyme disease

Encephalitis is inflammation of the brain parenchyma caused by a wide variety of infectious and noninfectious conditions. Anti– N -methyl-D-aspartate receptor (NMDAR) encephalitis is a recently described but increasingly recognized autoimmune disorder characterized by specific clinical features and the presence of anti-NMDAR antibodies in the cerebrospinal fluid (CSF) and serum. These autoantibodies appear to have an important role in the pathogenesis of the disease. This type of encephalitis is more prevalent in young women with ovarian teratomas, although it has also been described in adults and children of both sexes with and without identifiable neoplasms. Inspired by the case of our patient, a 19-year-old African American woman, we present a review of the literature regarding this noninfectious cause of acute encephalitis and discuss its relationship with tertomas.nn* HSVn : herpes simplex virus;n VZVn : varicella-zoster virus;n WNVn : West Nile virus;n CNSn : central nervous system;n ADEMn : acute disseminated encephalomyelitis;n NMDARn : N -methyl-D-aspartate receptor;n WBCn : white blood cells;n MRIn : magnetic resonance imaging;n CSFn : cerebrospinal fluid;n PCRn : polymerase chain reaction;n CDCn : Centers for Disease Control;n CTn : computed tomographic,n IgGn : immunoglobulin G;n FLAIRn : fluid-attenuated inversion recovery;n EEGn : electroencephalographic;n IgMn : immunoglobulin M;n IVIGsn : intravenous immunoglobulins

The Unintended Deleterious Consequences of the ‘Routine’ Urinalysis

Rhodococcus spp. are opportunistic pleomorphic aerobic gram-positive bacteria that usually cause infection in the context of hosts with cellular immune deficiency. Initially described as a common zoonotic pathogen in foals, infection in humans has been more commonly reported since the emergence of the AIDS epidemics. Pulmonary cavitary lesions are, by far, the most common clinical manifestation, but virtually any organ may be affected, usually because hematogenous spread of this bacterium. Clinically significant infection in immunocompetent hosts is a rare event, especially when the site of involvement is extrapulmonary. Primary brain Rhodococcal abscesses are very unusual and, to the best of our knowledge, they have never been documented in immunocompetent individuals in the absence of direct inoculation of the organism. We report a peculiar case of Rhodococcus spp. causing a primary brain abscess in an immunocompetent man. The clinician should be aware of potential laboratory pitfalls in the identification of Rhodococcus spp., as its diphtherioid morphology may prompt discarding the organisms as a contaminant. The importance of identifying the causative organism is paramount to adequately select antimicrobial therapy, particularly in the clinical setting of central nervous system (CNS) infection, where antibiotics are not only selected according to their bactericidal properties but also taking in consideration the blood-brain barrier permeability of the drug. Therefore, the optimal therapeutic approach of Rhodococcus spp. brain infections relies on surgical drainage plus relatively long-term multi-drug antimicrobial treatment, preferably based on drug sensitivity analysis. This article reviews the clinical and pathologic features of Rhodococcus spp. infection as an emerging opportunistic pathogenic organism in immunocompromised and immunocompetent individuals.