Antimicrobial chemotherapy of human infection due toListeria monocytogenes

Abstract

Listeriosis is an uncommon infection, but when it occurs it carries a high mortality rate. Early diagnosis is essential and thereafter appropriate antimicrobial chemotherapy. Ampicillin or penicillin plus gentamicin remains the treatment of choice for most manifestations of listeriosis, and adequate doses must be given, i.e. greater than 6g/day of ampicillin or penicillin. Co-trimoxazole appears to be an excellent alternative agent with good penetration into the cerebrospinal fluid. Vancomycin is an appropriate agent for the treatment of primary bacteraemia but does not cross the blood-brain barrier sufficiently well to be useful in meningitis, while erythromycin may be used to treat listeriosis in cases of pregnancy. Treatment of bacteraemia requires one to two weeks' therapy, while meningitis cases may need to be treated for longer; for example, it has been found that most patients with acute meningitis in the UK were treated for 20 days. Infective endocarditis needs treatment for six to eight weeks. Doses should be varied with patients' altered organ function and antimicrobial serum monitoring performed when appropriate.

Antimicrobial Activities against 84 Listeria monocytogenes Isolates from Patients with Systemic Listeriosis at a Comprehensive Cancer Center (1955-1997)

“…Plasmids carrying genetic determinants of antibiotic resistance can successfully transfer genetic code from Enterococcus faecalis to L. monocytogenes (2,4,19); this observation had raised serious concerns regarding emergence of antibiotic resistance and choice of optimal initial therapy for severe listeric infections in compromised individuals. Similar to this report, others have described no significant rise in drug-resistant L. monocytogenes (Table 3) (5,9,11,13,22,23). This may in part be due to the fact that most systemic listerosis is acquired from non-nosocomial environment pools, and hospital-acquired de novo invasive listerosis even in patients with severe immune deficiency is rare (10).…”

“…Penicillin and ampicillin are bactericidal against most strains of L. monocytogenes; however, in the preferred intracellular milieu, these microorganisms become more recalcitrant and on May 9, 2018 by guest http://jcm.asm.org/ even highly effective drugs are rendered bacteriostatic at best (7,9,15). The lack of in vivo bactericidal antilisteric effect becomes important in the treatment of systemic opportunistic infections in patients with compromised adaptive cellular immunity (10,20).…”

Avirulence of Viable But Non-Culturable Listeria monocytogenes cells demonstrated by in vitro and in vivo models

“…This gram-positive, psychrophilic bacterium can cause meningitis, abortion and perinatal septicemia in humans. Listeriosis is fatal in up to 30% of the cases [14,16].…”

Coselection of Cadmium and Benzalkonium Chloride Resistance in Conjugative Transfers from Nonpathogenic Listeria spp. to Other Listeriae

“…The single human pathogen in this genus, Listeria monocytogenes, continues to be associated with significant disease burden due to its high morbidity and mortality toward vulnerable populations such as the elderly, pregnant women and their fetuses, neonates, and immunocompromised patients (10,21,34,46). L. monocytogenes remains largely susceptible to antibiotics, with a common course for treatment being a combination of ampicillin and gentamicin (20). However, reported cases of listeriosis involving strains with multidrug resistance (6,17,38,40,52) suggest the potential for enhanced resistance through horizontal gene transfer with accompanying increases in public health concerns associated with this pathogen.…”