Follows invasive procedures or as a complication of appendicitis. Intra-abdominal: abscess or mass lesion.May cross anatomical boundaries to the mediastinum, pleura, bone, or chest wall.Thoracic: pneumonia or mass lesion +/- cavity or hilar adenopathy.Organisms may be present in cervical smears but do not represent infection.Ddx: tumor, endometritis, tubo-ovarian abscess, endometriosis.Presents with prolonged abdominal pain, vaginal bleeding or discharge and fever.Pelvic infection: classically, IUD-associated, with IUD in place > 1 yr.Osteoradionecrosis (necrosis associated with irradiation of the head and neck).Osteonecrosis of the jaw related to bisphosphonate therapy.Risk factors: poor oral hygiene, heavy alcohol use, and smoking.Infections are usually polymicrobial and may include abscess formation. This is the most common and classical presentation.Oral cervicofacial: characteristic 'lumpy jaw' with loss of temporomandibular jaw angle by swelling.Lesions of actinomycosis are often mistaken for tumor, especially in the lung, abdomen or bone.are weakly AFB positive upon this stain and is usually a disease of an immunocompromised host. It looks similar upon Gram staining, but Nocardia spp. Suspicion may be raised upon imaging studies that show infection crossing tissue planes (e.g., empyema crossing into the chest wall).Otherwise, Actinomyces may be part of routine oral or GI flora and not represent a true pathogen.Recovery is important if from typically uncontaminated sources, e.g., uncontaminated tissue, needle aspirates, OR detection of typical sulfur granules, etc.Diagnosis: characteristic Gram stain (filamentous or beaded branching rods) in tissue or sulfur granule with radiating Gram-positive bacilli seen on histopathology or exudate or in culture.Characteristic chronic lesion: dense fibrosis ('woody'), draining sinus with 'sulfur granules' that contain colonies of Actinomyces.Pelvic actinomycosis associated with IUDs.Abdominal actinomycosis associated with surgical procedures or IAI.May present with empyema, chest wall abscess.Thoracic: through aspiration, hematogenous or direct spread.Risk factors: alcohol, smoking, poor dentition.

Slowly progressing infection, often with granulomatous features categorized according to the body site.infection may advance through tissue planes with no respect for anatomical barriers. Also, in GI (distal esophagus), GU tract. The main niche is the oral cavity/pharynx.reside on mucosal surfaces and gain access to deeper tissues via surgical procedures, trauma, etc., disrupting the mucosal barrier. Nearly always part of a mixed infection, especially with flora such as Aggregatibacter (ex Actinobacillus) actinomycetemcomitans, Eikenella corrodens, Bacteroides spp, S.

Does keflex cover gram negative rods