Withholding iron from potential pathogens is a host defense strategy. There is evidence that iron overload per se compromises the ability of phagocytes to kill microorganisms. Several hypotheses exist to explain the association of hemochromatosis with infection. A combination of mechanisms likely contributes to the increase in susceptibility to infection in these patients. A review of the current literature delineating various pathogens to which patients with hemochromatosis are potentially susceptible, and recent advances in the understanding of the association of hemochromatosis with infection, are discussed.

Candida endophthalmitis is a sight-threatening manifestation of disseminated candidiasis. The occurrence of endogenous candida endophthalmitis in patients with candidemia has ranged from 0-45% in the published literature. In critically ill patients, it has even been associated with increased mortality. In recent years, use of newer antifungal therapies for invasive candidiasis has increased given the rise in infections with non-albicans species of Candida. To identify current practices of the management of endogenous candida endophthalmitis and relevant antifungal drug research in this disease state, we conducted a MEDLINE search (1967-2006) and bibliographic search of the English-language literature. Treatments for candida endophthalmitis have not been evaluated through well-designed, well-powered clinical trials. Data have mainly been presented in case reports, case series, animal studies, pharmacokinetic studies, and as small subsets of larger trials. Traditional systemic therapies have been amphotericin B with or without flucytosine or fluconazole. Cure rates with antifungal drugs alone appear to be much higher in patients with chorioretinitis than in endophthalmitis with vitreal involvement. Pars plana vitrectomy with or without intravitreal amphotericin B injections has been advocated particularly for patients with moderate-to-severe vitritis and substantial vision loss. Information on new antifungal agents for endophthalmitis is limited, despite increasing use in patients with candidemia. Voriconazole may be a particularly attractive agent to consider for infections with fluconazole-resistant, voriconazole-susceptible strains. The current patchwork of animal studies and small patient reports provide clinicians with some insight into the role of newer agents in the treatment of candida endophthalmitis. In general, it appears that chorioretinitis infections can be more readily cured with most systemic antifungal agents, whereas more aggressive treatment, often including vitrectomy with or without intra-vitreal antifungal administration, is needed for patients with endophthalmitis with vitritis.

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ᰔMycobacterium mageritense is an uncommon cause of catheter-related bacteremia (1, 4).We report a 26-year-old pregnant woman who presented with fever for 3 weeks. A tunneled central venous catheter (CVC) had been placed due to hyperemesis. The patient did not have any immunocompromised conditions. Blood cultures were performed by use of BACTEC Aerobic Plus and Anaerobic Lytic. Anaerobic cultures from both the central line and a peripheral site showed beaded gram-positive rods. The time to detection was 103 h. A modified acid-fast stain was highly suggestive of a nontuberculous mycobacterium (NTM) which was identified as Mycobacterium mageritense by DNA sequencing. Susceptibility studies performed by a broth dilution MIC method showed the organism to be susceptible to ciprofloxacin (MIC, 0.5 g/ml) and trimethoprim-sulfamethoxazole (TMP-SXT) (MIC, 0.5 and 9.5 g/ml, respectively) and resistant to amikacin (MIC, 128 g/ml) and clarithromycin (MIC, Ͼ64 g/ml). The breakpoints were determined according to standards of the Clinical and Laboratory Standards Institute (CLSI).Intravenous TMP-SXT was initiated. The catheter was removed 1 week later, and the tip was cultured using the roll plate technique on sheep blood agar. No growth was observed after 5 days of incubation. The patient was treated for 2 weeks with intravenous TMP-SXT, with complete resolution of her symptoms.To our knowledge, this is the second reported case in the literature of a CVC-related bloodstream infection due to Mycobacterium mageritense. The first reported case occurred in a 32-year-old immunocompromised woman who was treated with linezolid and amikacin.Clinical disease produced by M. mageritense is uncommon and ranges from skin and soft tissue infection to health careassociated infections (4). It is a nonpigmented, rapidly growing mycobacterium, closely resembling the M. fortuitum third biovariant complex (2, 4). The source of M. mageritense in our case remains unclear.Although bloodstream infection with NTM usually occurs in immunocompromised patients with CVC, our case occurred in a patient with no immunocompromised state. The catheter tip did not grow the organism, which may be due to the patient's prior antimicrobial therapy. Also, since this catheter was cultured using the roll plate technique (which detects only extraluminal colonization), intraluminal colonization, frequently seen with long-term catheters, was not detected. CVC infection is documented with a positive catheter tip in only 15 to 25% of cases with presumptive CVC-related infection. There are no treatment guidelines for NTM bloodstream infections.The decision to remove the catheter from our patient was based on previously reported cases of M. fortuitum bacteremia in which a high relapse rate was seen if catheters were not removed (3).The susceptibility pattern of this isolate of M. mageritense resembles that of the M. fortuitum group. Given that isolates of M. mageritense have growth, biochemical, and drug susceptibility patterns of the M. fortuitum third biovariant complex, i...