Pericarditis due to Neisseria meningitidis serogroup W135.

Neisseria meningitidis is a well-recognized cause of bacterial meningitis. Although less common, N. meningitidis can also involve extra-meningeal sites, including the pericardium. The frequency of such extra-meningeal clinical manifestations differs depending on N. meningitidis serogroup. N. meningitidis serogroups C and W135 have been reportedly associated with extra-meningeal meningococcal disease more frequently including pericarditis. In general, meningococcal pericarditis is categorized into three etiologies; primary meningococcal disease, secondary disease due to disseminated meningococcemia, and reactive form as an immunologic complication. Importantly, meningococcal pericarditis can cause massive pericardial effusion with cardiac tamponade that can lead to cardiogenic shock. We report a case of pericarditis due to N. meningitidis serogroup W135 secondary to disseminated meningococcal disease.

Cellulitis and Bacteremia due to Neisseria weaveri following a dog bite.

Neisseria weaveri is a gram-negative rod that can cause skin and soft tissue infections associated with dog bites. Although N. weaveri is a less well recognized zoonotic Neisseria species, its potential pathogenicity merits recognition since N. weaveri can cause severe septicemia in humans.

The Effective Duration of Antimicrobial Activity of Mafenide Acetate After Reconstitution.

Mafenide acetate is an effective but costly antimicrobial solution used for burn wounds. The package insert instructs the user to discard unused solution within 48 hours of opening. The purpose of this study is to evaluate the antimicrobial activity of mafenide acetate beyond 48 hours after reconstitution, to possibly reduce cost by eliminating product waste. Staphylococcus aureus and Pseudomonas aeruginosa isolates were used to seed Mueller-Hinton agar plates. Filter paper disks were then saturated with 5% mafenide acetate at 0, 2, 7, 14, 30, and 60 days after reconstitution. Disks were then placed on the seeded agar plates and incubated. After incubation, the zone of inhibition around each plate was measured. A zone of inhibition of 2 mm or greater was indicative of susceptibility. Mafenide acetate remained efficacious, with a zone of inhibition of >2 mm to both organisms at 0, 2, 7, 14, 30, and 60 days after mafenide acetate reconstitution. This in vitro study demonstrates that the antimicrobial activity of mafenide acetate remains present for at least 60 days after reconstitution. Unused mafenide may not need to be discarded at 48 hours after opening. Reducing wasted product has the potential to translate into cost savings.

Hydrofiber Dressing Saturated With Mafenide Acetate Extends the Duration of Antimicrobial Activity.

Mafenide acetate is used in some burn wounds for its ability to penetrate eschar but requires frequent uncomfortable dressing changes for its application. The authors hypothesize that hydrofiber dressings will hold mafenide acetate solution for an extended period of time and maintain antimicrobial activity longer than traditional gauze, thus possibly obviating the need for frequent dressing changes. Four experimental arms included: 1) hydrofiber, stored on a dry well plate as control, 2) gauze saturated with 2.5% mafenide acetate, stored on nonsterile porcine skin, 3) hydrofiber saturated with mafenide acetate, stored on dry well plate, and 4) hydrofiber saturated with mafenide acetate, stored on nonsterile porcine skin. At 0, 24, 48, and 72 hours, a 1-cm disk was cut from the dressing sheet of each study arm, placed on agar plates seeded with Staphylococcus aureus and Pseudomonas aeruginosa, and incubated for 24 hours, and the zone of inhibition was measured. A zone of 2 mm or greater was indicative of susceptibility. Each arm of the experiment was performed four times to demonstrate reproducibility. Plain hydrofiber (control) demonstrated no zone of inhibition at any time point, thereby possessing no antimicrobial activity alone. Gauze saturated with mafenide acetate did not reliably demonstrate antimicrobial activity beyond 0 hours. Hydrofiber saturated with mafenide acetate, whether stored on a dry well plate or nonsterile porcine skin, consistently possessed sustained antimicrobial activity as demonstrated by zones of inhibition greater than 2 mm to both S. aureus and P. aeruginosa. Mafenide acetate-soaked hydrofiber dressings stay moist and maintain antimicrobial activity against S. aureus and P. aeruginosa for at least 72 hours without repeated soaks.

Necrotizing retinitis due to syphilis in a patient with AIDS.

The ocular manifestations of syphilis are varied. Ocular syphilis can occur during any stage of infection and involve virtually any part of the eye. In immunocompetent individuals, the most common etiologies include syphilitic uveitis. Although the clinical presentation of ocular syphilis in HIV-infected patients is also widespread, posterior segment involvement has been more commonly described particularly in patients with AIDS. The diagnosis of syphilitic retinitis is challenging since its clinical presentation mimics retinitis caused by other viral etiologies. In addition, HIV-infected individuals with syphilis are more likely to develop aberrant serologic responses. Recognition of syphilitic retinitis and prompt initiation of penicillin therapy is of critical importance since syphilitic retinitis generally responds well to treatment and loss of vision is reversible. In this report, we describe a 39-year-old female with advanced stages of AIDS who developed necrotizing retinitis due to syphilis. Prompt initiation of intravenous penicillin led to excellent visual outcome for this patient despite significantly decreased visual acuity on presentation.

Acalculous Cholecystitis Due to Histoplasma capsulatum in a Patient With HIV Infection.

Although acalculous cholecystitis typically occurs in critically ill individuals, it has been described in patients with HIV infection. Recognition of AIDS-related acalculous cholecystitis is important for gastroenterologists to provide optimal therapy, since many different opportunistic pathogens may be involved. Histoplasma capsulatum causes a wide spectrum of infectious sequelae, including disseminated histoplasmosis in patients with HIV infection, but biliary tract involvement has been described infrequently. We present a case of acalculous cholecystitis caused by H. capsulatum in a patient with HIV infection.

Intracellular Pathogens within Alveolar Macrophages in a Patient with HIV Infection: Diagnostic Challenge.

In HIV-infected individuals, macrophages, the key defense effector cells, manifest defective activity in their interactions with a wide variety of opportunistic pathogens, including fungi and protozoa. Understanding the morphological characteristics of intracellular opportunistic pathogens in addition to their pathogenesis is of critical importance to provide optimal therapy, thereby decreasing morbidity and mortality in HIV-infected patients. We herein present a case of disseminated histoplasmosis confused with disseminated visceral leishmaniasis in an HIV-infected individual from Guyana who developed intracellular organisms within alveolar macrophages.

Relationships between renal parameters and serum and urine markers of inflammation in those with and without HIV infection.

We sought to determine the relationships among intrarenal and systemic inflammation and renal disease in HIV. We compared paired serum and urinary levels (normalized to urine creatinine) of monocyte chemotactic protein-1 (MCP-1), regulated on activation normal T cell expressed and secreted (RANTES), interferon-γ-induced protein-10 (IP-10), interleukin-8 (IL-8), and ß2-microglobulin (B2M) between two groups of HIV-infected subjects not receiving antiretroviral therapy (ART) [A: not expecting to initiate ART immediately due to having CD4 cell counts ≥350/µl, N=26; B: about to initiate ART, N=19], a group of HIV-infected subjects receiving virologically suppressive antiretroviral therapy [C, N=30], and a group of HIV-uninfected, healthy volunteers [D, N=45]. We then correlated these inflammatory biomarker levels with urine protein/creatinine ratios (uPCR), urine albumin/creatinine ratios (uACR), and estimated glomerular filtration rates (eGFR). Urine inflammatory biomarker levels were highest in Group B. When combining all four study groups, statistically significant positive correlations included uPCR with urine IL-8, urine MCP-1, urine IP-10, and serum IP-10 and uACR with urine IL-8, urine B2M, serum IP-10, and serum B2M. eGFR was statistically significantly negatively correlated with serum MCP-1 and serum B2M. Paired serum and urine levels of IP-10 and B2M (but not IL-8, RANTES, or MCP-1) were significantly correlated with each other in the overall group. The levels of urine inflammatory markers tested differed by HIV status and use of virologically suppressive ART. These urine and serum inflammatory markers were differentially correlated with uPCR, uACR, and eGFR, suggesting that different intrarenal and systemic inflammatory pathways may contribute to different measures of nephropathy.

Clostridium paraputrificum Bacteremia Associated with Colonic Necrosis in a Patient with AIDS.

Clostridium species are anaerobic Gram-positive rods that can cause a broad range of invasive infections in humans, including myonecrosis and bacteremia. Importantly, clostridial bacteremia is frequently associated with underlying medical conditions, such as colonic malignancy. Characterizing Clostridium spp. and understanding their associated clinical disease spectrum are paramount to provide optimal treatment, thereby decreasing morbidity and mortality especially in those with underlying debilitating comorbidities. Clostridium paraputrificum is an infrequently isolated Clostridium species and its clinical significance has not been well described. We herein report a case of bacteremia due to C. paraputrificum in a 65-year-old man with AIDS who developed acute colonic necrosis complicated by septic shock. We then review other cases of bacteremia associated with C. paraputrificum in the literature in addition to discussing the clinical significance of anaerobic bacteremia in general. To our knowledge, our report is the second case of C. paraputrificum bacteremia in a patient with AIDS.

Osteomyelitis caused by Achromobacter xylosoxidans.

Achromobacter xylosoxidans is an aerobic, nonfermenting gram-negative rod and described as a waterborne bacterium since it habits aquatic environments ubiquitously. It has frequently been isolated from aquatic surroundings in the hospital and from various human body sites. Although occasionally considered a non-pathogen, A. xylosoxidans has been associated with outbreaks of nosocomial infection due to contaminated fluids. Moreover, a wide variety of infectious etiologies due to A. xylosoxidans has been reported primarily in immunocompromised individuals. Heightened awareness of this bacterium and associated clinical importance is warranted for clinicians since its broad disease spectrum in humans and frequent multi-drug resistance may result in an increased mortality rate. In this report, we describe a case of osteomyelitis caused by A. xylosoxidans in a patient with a history of diabetes mellitus.

Bacteremia due to Elizabethkingia meningoseptica.

Elizabethkingia meningoseptica is a nonfermentative gram-negative bacillus that is ubiquitously found in hospital environments and as such, it has been associated with various nosocomial infections. Immunocompromised individuals are particularly at increased risk for developing severe infections due to E. meningoseptica, including bacteremia. E. meningoseptica is resistant to multiple antimicrobials commonly used for gram-negative bacteria and conventional empirical antimicrobials targeting those organisms may result in unfavorable outcome. We report a case of bacteremia due to E. meningoseptica in a patient who necessitated chronic hemodialysis therapy to heighten awareness of this emerging pathogen among patients on hemodialysis.

Ramsay Hunt syndrome and zoster laryngitis with multiple cranial nerve involvement.

Ramsay Hunt syndrome is characterized by varicella zoster virus infection affecting the geniculate ganglion of the facial nerve. It typically presents with vesicles in the external auditory canal associated with auricular pain and peripheral facial nerve paralysis. Although vestibulocochlear nerve is frequently co-involved during the course of Ramsay Hunt syndrome, multiple lower cranial nerve involvement has rarely been described in the literature. In addition, laryngitis due to varicella zoster virus is a diagnostic challenge due to its unfamiliarity among clinicians. We report a case of Ramsay Hunt syndrome with laryngitis involving multiple lower cranial nerves.