Background: The etiology of community-acquired pneumonia (CAP) has evolved since the beginning of the antibiotic era. Recent guidelines encourage immediate empiric antibiotic treatment once a diagnosis of CAP is made. Concerns about treatment recommendations, on the one hand, and antibiotic stewardship, on the other, motivated this review of the medical literature on the etiology of CAP. Methods: We conducted a systematic review of English-language literature on the etiology of CAP using methods defined by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched PubMed using a combination of the keywords ‘pneumonia’, ‘CAP’, ‘etiology’, ‘microbiology’, ‘bacteriology’, and ‘pathogen’. We examined articles on antibiotics that were develop to treat pneumonia. We reviewed all ‘related articles’ as well as studies referenced by those that came up in the search. After we excluded articles that did not give sufficient microbiological data or failed to meet other predetermined criteria, 146 studies remained. Data were stratified into diagnostic categories according to the microbiologic studies that were done; results are presented as the percentage in each category of all cases in which an etiology was established. Results: Streptococcus pneumoniae remains the most common cause of CAP although declining in incidence; this decline has been greater in the US than elsewhere. Haemophilus influenzae is the second most common cause of CAP, followed by Staphylococcus aureus and Gram negative bacilli. The incidence of all bacteria as causes of CAP has declined because, with routine use of PCR for viruses, the denominator, cases with an established etiology, has increased. Viruses were reported on average in about 10% of cases, but recent PCR-based studies identified a respiratory virus in about 30% of cases of CAP, with substantial rates of viral/bacterial coinfection. Conclusion: The results of this study justify current guidelines for initial empiric treatment of CAP. With pneumococcus and Haemophilus continuing to predominate, efforts at antibiotic stewardship might be enhanced by greater attention to the routine use of sputum Gram stain and culture. Because viral/bacterial coinfection is relatively common, the identification of a virus by PCR does not, by itself, allow for discontinuation of the antibiotic therapy.

Purpose: To compare laser intra-hemorrhoidal coagulation with Milligan–Morgan (MM) hemorrhoidectomy. Method: Patients with symptomatic grade II or III internal hemorrhoids according to the Goligher's classification (refractory to medical treatment) were enrolled in this double-blinded randomized controlled trial study. In the laser group, hemorrhoidal columns were coagulated using a 980-nanometer (nm) radial laser emitting fiber (three, 15-W pulses of 1.2 s each, with 0.6-s intervals). Operative time, postoperative pain and complications, and recovery or resolution of symptoms were measured. Patients were followed up for at least one year for evaluating healing, resolution of symptoms, and late complications. Results: Postoperative pain scores (at 12, 18, and 24 hr after surgery) were significantly lower in the laser group compared with the MM group (p <.01). The operative time and intra-operative blood loss were more in the MM group (p <.001). The administration of analgesics was significantly reduced in the laser group (p <.05). Two patients in the laser group were presented with thrombosis of external hemorrhoid 7–10 days after the procedure, which was resolved with medical treatment, but no patients in the MM group developed hemorrhoidal thrombosis (p >.05). One-year follow-up showed comparable results in terms of the resolution of symptoms and sustainable cure. Conclusions: Intra-hemorrhoidal coagulation with 980-nm diode laser reduces postoperative pain, intra-operative bleeding, and administered analgesics with a comparable resolution rate of hemorrhoid symptoms. However, for the patients who experience complications, such as hemorrhoidal thrombosis, the overall pain may be equivalent to or even worse than conventional hemorrhoidectomy.