Penicillin Allergy Label Is Associated With Worse Clinical Outcomes in Bacterial Pneumonia

BACKGROUND

Penicillins (PCNs) are a first-line treatment option for bacterial pneumonia. PCN allergy label can delay antimicrobial treatment and result in the use of alternative antibiotic regimens risking an inadequate response to treatment and potentially increased adverse drug reactions.

OBJECTIVE

To investigate the impact of PCN allergy label on clinical outcomes of bacterial pneumonia.

METHODS

This retrospective cohort study used TriNetX, a web-based tool for population cohort research, to identify adult patients with and without PCN allergy label diagnosed with bacterial pneumonia. Cohorts were matched for baseline demographics and chronic medical conditions. The 30-day risks of hospitalization, acute respiratory failure, intubation, need for intensive level of care, and mortality were compared. Antibiotics used and their possible adverse reactions were explored.

RESULTS

After matching, there were 68,748 patients in each cohort. Patients with bacterial pneumonia with PCN allergy label had higher risks of hospitalization (risk ratio [RR], 1.23; 95% confidence interval [CI], 1.22-1.24), acute respiratory failure (RR, 1.14; 95% CI, 1.12-1.15), intubation (RR, 1.18; 95% CI, 1.13-1.22), intensive level of care (RR, 1.11; 95% CI, 1.08-1.14), and mortality (RR, 1.08; 95% CI, 1.04-1.13) compared with patients without PCN allergy label. Patients with PCN allergy label had decreased use of PCNs and cephalosporins and increased utilization of other antibiotic classes compared with patients without PCN allergy label. PCN allergy label was also associated with increased risk of adverse drug reactions.

CONCLUSION

PCN allergy label is associated with worse clinical outcomes in bacterial pneumonia, and risk mitigation strategies should be considered.

Electronic cigarette vapour increases virulence and inflammatory potential of respiratory pathogens

INTRODUCTION

Bacteria have been extensively implicated in the development of smoking related diseases, such as COPD, by either direct infection or bacteria-mediated inflammation. In response to the health risks associated with tobacco exposure, the use of electronic cigarettes (e-cigs) has increased. This study compared the effect of e-cig vapour (ECV) and cigarette smoke (CSE) on the virulence and inflammatory potential of key lung pathogens (Haemophilus influenzae, Streptococcus pneumoniae, Staphylococcus aureus and Pseudomonas aeruginosa).

METHODS

Biofilm formation, virulence in the Galleria mellonella infection model, antibiotic susceptibility and IL-8/TNF-α production in A549 cells, were compared between bacteria exposed to ECV, CSE and non-exposed bacteria.

RESULTS

Statistically significant increases in biofilm and cytokine secretion were observed following bacterial exposure to either ECV or CSE, compared to non-exposed bacteria; the effect of exposure to ECV on bacterial phenotype and virulence was comparable, and in some cases greater, than that observed following CSE exposure. Treatment of A549 cells with cell signaling pathway inhibitors prior to infection, did not suggest that alternative signaling pathways were being activated following exposure of bacteria to either ECV or CSE.

CONCLUSIONS

These findings therefore suggest that ECV and CSE can induce changes in phenotype and virulence of key lung pathogens, which may increase bacterial persistence and inflammatory potential.

Differential Toll-Like Receptor-Signalling of Burkholderia pseudomallei Lipopolysaccharide in Murine and Human Models

The Gram-negative bacterium Burkholderia pseudomallei causes melioidosis and is a CDC category B bioterrorism agent. Toll-like receptor (TLR)-2 impairs host defense during pulmonary B.pseudomallei infection while TLR4 only has limited impact. We investigated the role of TLRs in B.pseudomallei-lipopolysaccharide (LPS) induced inflammation. Purified B.pseudomallei-LPS activated only TLR2-transfected-HEK-cells during short stimulation but both HEK-TLR2 and HEK-TLR4-cells after 24 h. In human blood, an additive effect of TLR2 on TLR4-mediated signalling induced by B.pseudomallei-LPS was observed. In contrast, murine peritoneal macrophages recognized B.pseudomallei-LPS solely through TLR4. Intranasal inoculation of B.pseudomallei-LPS showed that both TLR4-knockout(-/-) and TLR2x4-/-, but not TLR2-/- mice, displayed diminished cytokine responses and neutrophil influx compared to wild-type controls. These data suggest that B.pseudomallei-LPS signalling occurs solely through murine TLR4, while in human models TLR2 plays an additional role, highlighting important differences between specificity of human and murine models that may have important consequences for B.pseudomallei-LPS sensing by TLRs and subsequent susceptibility to melioidosis.

[ORGANIZED PNEUMONIA IN A PATIENT WITH ULCERATIVE COLITIS]

The article presents a case of organized pneumonia development in 44-year-old patient with ulcerative colitis, successfully permitted on the background of treatment with high doses of systemic steroids. The authors consider the case as extra-intestinal IBD-associated pulmonary disease.

Proton pump inhibitors: bacterial pneumonia

After two decades of widespread use, proton pump inhibitors are considered to have a very well-documented and acceptable adverse effect profile in the short-term. Yet adverse effects continue to emerge. In particular, epidemiological studies conducted over the past 10-12 years showed an increased incidence of fractures. New data now point to an increased risk of bacterial pneumonia. A Korean meta-analysis published in 2011 showed a statistically significant increase in the risk of bacterial pneumonia in patients taking proton pump inhibitors, with an odds ratio of 1.27 (95% confidence interval (95% CI): 1.11 to 1.46). The increase in community-acquired pneumonia was also statistically significant, with an odds ratio of 1.34 (95% CI: 1.14 to 1.57). This is consistent with the results of a meta-analysis published in 2010, which gave an odds ratio of 1.36 (95% CI: 1.12 to 1.65). The increase in the frequency of bacterial pneumonia was highest during the first week of treatment, with an odds ratio of 3.95 (95% CI: 2.86 to 5.45). Subsequent studies have provided conflicting results. Possible mechanisms include bacterial passage into the lungs after colonisation of the upper gastrointestinal tract resulting from the reduction in gastric acidity; bacterial overgrowth in the lungs due to a change in the pH of respiratory secretions; and impaired neutrophil phagocytic function. The available data suggest that proton pump inhibitors play a role in the increased frequency of bacterial pneumonia in treated patients. Similar data implicating H2 receptor antagonists and the proposed mechanism (acid suppression) imply that there are no alternative acid-suppressive medications. This risk of pneumonia is yet another reason not to trivialise the use of proton pump inhibitors. These drugs should only be used when the likely benefits clearly outweigh the potential harms.

A severe complication of anti-TNF alfa treatment

The antitumor necrosis factor (TNF-alpha) drugs are increasingly used in treating skin diseases such as psoriasis. TNF-alpha is a proinflammatory cytokine with a key role in the pathogenesis of psoriasis but also in host defence against bacterial pathogens, especially against those that multiply inside host cells. The effectiveness of anti-TNF-alpha in the treatment of psoriasis is now widely recognized and has led to their increasingly wide use. Although these drugs are considered relatively safe, their use is associated with an increased incidence of serious infections even in patients treated. Have been described above numerous cases of tuberculosis but has also observed an increased incidence of granulomatous infections by intracellular bacteria such as Legionella pneumophila required. Infections due to this biotic agent, if not diagnosed early, are potentially fatal. We report the case of a patient, heavy smoker, suffering from severe skin psoriasis who after starting treatment with infliximab developed a pneumonia caused by Legionella pneumophila. Our aim is to draw the attention of specialists on increasing risk of granulomatous infections by intracellular agents in patients being treated with anti TNF-alpha.

Acute alcohol intake impairs lung inflammation by changing pro- and anti-inflammatory mediator balance

Previous studies have shown that alcohol (ethanol [EtOH]) intoxication impairs lung immunity by affecting cytokines pivotal to the inflammatory process. The objective of this study was to test the hypothesis that acute alcohol intoxication impairs lung innate immunity by downregulating the expression of proinflammatory mediators while simultaneously upregulating anti-inflammatory mediators. EtOH was administered to the mice 0.5h prior to an intratracheal injection of Escherichia coli lipopolysaccharide (LPS). The animals were killed either 4 or 24h after LPS to recover plasma, lungs, and bronchoalveolar lavage fluid. Lung inflammatory cytokines tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1beta), IL-6, macrophage inhibitory factor (MIF), IL-10, TGF-beta, and receptors for TNF-alpha, IL-1beta, IL-6, and TGF-beta as well as glycoprotein (gp)130 and corticosterone (CS) levels were evaluated at mRNA and protein level. While the mRNA expression and the soluble TNF-Rp55 levels were significantly upregulated by EtOH, LPS-induced TNF-alpha activity, TNF-Rp55 mRNA expression, and soluble TNF-Rp55 levels were significantly suppressed. The LPS-induced expression of IL-1beta, IL-6, MIF, gp130, and receptors IL-1RI, IL-1RII, and IL-6Ralpha were also significantly impaired by EtOH. EtOH increased significantly the basal IL-10 activity at 3h, which continued to remain elevated even at 24h. The EtOH effect on IL-10 activity persisted even in LPS-challenged mice. EtOH and LPS augmented lung CS levels independently of each other. EtOH suppressed upregulation of TGF-beta1 mRNA expression by LPS and blocked completely LPS-induced TGF-beta1 secretion. In conclusion, the data suggest that the suppression of acute lung inflammation by EtOH intoxication is largely due to impairment by EtOH of proinflammatory cytokine signaling at the levels of cytokine expression and secretion as well as receptor expression and soluble receptor activity. The augmentation by EtOH of anti-inflammatory mediators' secretion most likely shifts the cytokine balance in the anti-inflammatory direction.

Involvement of semicarbazide-sensitive amine oxidase-mediated deamination in lipopolysaccharide-induced pulmonary inflammation

Semicarbazide-sensitive amine oxidase (SSAO) resides on the vascular endothelium and smooth muscle cell surface and is capable of deaminating short chain aliphatic amines and producing toxic aldehydes and hydrogen peroxide. The enzyme, also known as a vascular adhesion protein-1, is involved in the inflammation process. This intriguing protein with dual functions is increased in the serum of diabetic and heart failure patients. In the present study we assessed the involvement of SSAO in a lipopolysaccharide-induced pulmonary inflammation model using transgenic mice that overexpress human vascular adhesion protein-1. Overexpression of SSAO activity increased the formation of protein-formaldehyde deposits in tissues. Lysine residues of proteins were the primary targets for cross-linkage with formaldehyde derived from deamination of methylamine. Lipo-polysaccharide-induced increases in inflammatory cells in the bronchoalveolar lavage (BAL) fluid were significantly higher in the transgenic than in the nontransgenic mice. BAL cell counts were also higher in the untreated transgenic than in nontransgenic mice. Blocking SSAO activity with a selective inhibitor significantly reduced the number of neutrophils as well as levels of macrophage inflammatory protein-1alpha, granulocyte colony-stimulating factor, tumor necrosis factor-alpha, and interleukin-6 in the BAL fluid. Inhalation of methylamine also increased BAL neutrophil counts. Together, these results suggest a role for SSAO-mediated deamination in pulmonary inflammation.

Fatal staphylococcal sepsis in Crohn's disease after infliximab

We report a case of a 40-year-old woman who had received infliximab for perianal Crohn's disease. After six infusions of infliximab, the patient developed staphylococcal pneumonia resulting in fatal adult respiratory distress syndrome. The case is discussed in the context of the toxicity profile of infliximab.

Pulmonary infiltrates in patients receiving long-term glucocorticoid treatment: etiology, prognostic factors, and associated inflammatory response

BACKGROUND

Glucocorticoid treatment alters immunoregulatory defense mechanisms and may therefore favor the development of different pulmonary infections.

METHODS

The etiology, prognostic factors, and associated inflammatory response of pulmonary infiltrates in 33 patients receiving long-term glucocorticoid treatment (LTGCT) were prospectively evaluated.

RESULTS

Aspergillus spp (n = 9, 31%) and Staphylococcus spp (n = 6, 21%) were the most common causative agents. Using different diagnostic techniques, we obtained a specific diagnosis in 28 of 33 episodes (85%) of pulmonary infiltrates. Bronchoscopic techniques provided the diagnosis in 64% of the cases. Crude mortality was 45%. Variables associated with mortality were as follows: age > 64 years, bilateral radiographic involvement, delay in diagnosis, inappropriate empirical treatment, Simplified Acute Physiology Score (SAPS) II > or = 25, and requirement for mechanical ventilation (MV). SAPS II > or = 25 (odds ratio [OR], 16; 95% confidence interval, 1 to 260) and MV requirement (OR, 50; 95% confidence interval, 2 to 360) were also significant on multivariate analysis. Pulmonary infections were associated with an increase in the concentration of relevant inflammatory cytokines such as tumor necrosis factor-alpha and interleukin-6 both in serum and BAL. This local and systemic inflammatory response was attenuated when compared with the response observed in patients with pulmonary infections but without glucocorticoid treatment or receiving glucocorticoids for a short period of time (< 9 days).

CONCLUSIONS

Pulmonary infiltrates in patients receiving LTGCT are often caused by fungi and Gram-positive cocci, and are associated with attenuated local and systemic inflammatory response. Although in most cases, sputum cultures and bronchoscopic techniques are diagnostic, the associated mortality is high, particularly in those requiring MV.

Mycobacterium xenopi pulmonary infection in an HIV infected patient under highly active antiretroviral treatment

Highly active antiretroviral therapy (HAART) is responsible for a striking reduction in AIDS related morbidity and mortality by partly restoring immune function. However, HAART can also precipitate the development of clinically apparent opportunistic infections in patients with latent infections. We report a case of an HIV infected patient who developed granulomatous nodular and cavitatory lesions of the lungs due to Mycobacterium xenopi as a manifestation of the immune restoration syndrome.

Pulmonary nocardiosis during immunosuppressive therapy for idiopathic pulmonary fibrosis

Nocardiosis is a subacute or chronic suppurative infection caused by Nocardia species. Although it is more common in immunocompromised hosts, idiopathic pulmonary fibrosis (IPF) has not been recognized as a predisposing factor for nocardial infection. We report a case of IPF, in which pulmonary nocardiosis developed during treatment with prednisolone and cyclophosphamide. The risk of pulmonary nocardiosis may be increased in cases of IPF on immunosuppressive therapy. Since IPF often accompanies lung carcinoma, it is important to correctly differentiate nocardiosis from carcinoma.