Alcohol abuse and Streptococcus pneumoniae infections: consideration of virulence factors and impaired immune responses

Abstract

Alcohol is the most frequently abused substance in the world. Both acute and chronic alcohol consumption have diverse and well documented effects on the human immune system, leading to increased susceptibility to infections like bacterial pneumonia. S. pneumoniae is the most common bacterial etiology of community acquired pneumonia world-wide. The frequency and severity of pneumococcal infections in individuals with a history of alcohol abuse is much higher than the general population. Despite this obvious epidemiological relevance, very few experimental studies have focused on the interaction of pneumococci with the immune system of a host acutely or chronically exposed to alcohol. Understanding these host-pathogen interactions is imperative for designing effective prophylactic and therapeutic interventions for such populations. Recent advances in pneumococcal research have greatly improved our understanding of pneumococcal pathogenesis and virulence mechanisms. Additionally, a large body of data is available on the effect of alcohol on the physiology of the lungs and the innate and adaptive immune system of the host. The purpose of this review is to integrate the available knowledge in these diverse areas of for a better understanding of the how the compromised immune system derived from alcohol exposure responds to pneumococcal infections.

Alcohol, Liver, Systemic Inflammation and Skin: A Focus on Patients with Psoriasis

“…Thus, the measurement of cytokines may have a diagnostic value in psoriatics with alcohol consumption. Alcohol is not only capable of enhancing the inflammatory state in these individuals, but might also inhibit the functions of cells that destroy invading microorganisms resulting in increased susceptibility to infections [70]. Streptococcal infections of the throat can trigger an outbreak of guttate psoriasis showing that this increased susceptibility may be involved in disease onset and progression.…”

Effects of sodium methyldithiocarbamate on selected parameters of innate immunity and clearance of bacteria in a mouse model of sepsis

“…We confirmed the results reported by Ebino et al that this method leads to uniform distribution of a hydrophilic compound (such as methylene blue) throughout both lungs (results not shown). Administration of SMD by either route was followed 15 min later by intraperitoneal injection of non-pathogenic E. coli (2 × 10 8 /200 µl) as described previously [3,14]. Body temperature was monitored using an anal thermistor probe and an electronic digital thermometer for 72 h and the number of survivors was counted.…”

M2b Monocytes Provoke Bacterial Pneumonia and Gut Bacteria–Associated Sepsis in Alcoholics

“…Pneumonia and gut bacteria-associated sepsis, caused by microbes that are normally distributed in the upper respiratory tracts (pneumonia) and the upper and lower intestine (bacterial translocation), are seen frequently in alcoholics (3)(4)(5)(6). In this study, the host antibacterial resistance of alcoholics to Klebsiella pneumonia and sepsis stemming from E. faecalis translocation was investigated in a humanized murine model of alcoholics.…”

“…A lcohol abuse is associated with a variety of health problems (e.g., liver diseases and cancer), and alcoholics have an increased risk for serious infectious complications, such as pulmonary and gut bacteria-associated infections (1)(2)(3)(4)(5). The majority of the causative pathogens in these infections in alcoholics are microbes normally found in the upper respiratory tracts (staphylococci, Klebsiella) and the upper and lower intestine (enterococci, Clostridium, Pseudomonas) (3-6).…”