Bacterial Infections Chapter 14
Infections Caused by Gram Positive Organisms.
Michael Hohnadel, D.O. 10/7/03
1 •Staphylococcal Infections
• General • 20% of adults are nasal carriers. • HIV infected are more frequent carriers.
• Lesions are usually pustules, furuncles or erosions with honey colored crust. • Bullae, erythema, widespread desquamation possible. • Embolic phenomena with endocarditis: • Olser nodes • Janeway Lesions
2 Embolic Phenomena With Endocarditis
•
Osler nodes Janeway lesion
3 Superficial Pustular Folliculitis
• Also known as Impetigo of Bockhart • Presentation: Superficial folliculitis with thin wall, fragile pustules at follicular orifices. – Develops in crops and heal in a few days. – Favored locations: • Extremities and scalp • Face (esp periorally) • Etiology: S. Aureus.
4 Sycosis Vulgaris (Sycosis Barbae) • Perifollicular, Chronic , pustular staph infection of the bearded region. • Presentation: Itch/burn followed by small, perifollicular pustules which rupture. New crops of pustules frequently appear esp after shaving. • Slow spread. • Distinguishing feature is upper lip location and persistence. – Tinea is lower. – Herpes short lived – Pseudofolliculitis Barbea ingrown hair and papules.
5 Sycosis Vulgaris
6 Sycosis Lupoides
• Staph infection that through extension results in central hairless scar surrounded by pustules. Pyogenic folliculitis and perifolliculitis with deep extension into hair follicles often with edema. • Thought to resemble lupus vulgaris in appearance. • Etiology: S. Aureus
7 Treatment of Folliculitis
• Cleansing with soap and water. • Bactroban (Mupirocin) • Burrows solution for acute inflammation. • Antibiotics: cephalosporin, penicillinase resistant PCN.
8 Furunculosis
• Presentation: Perifollicular, round, tender abscess that ends in central suppuration. • Etiology: S. Aureus • Breaks in skin integrity is important. – Various systemic disorders may predispose. • Hospital epidemics of abx resistant staph may occur – Meticulous hand washing is essential.
9 Furuncle
10 Furuncle / Carbuncle
11 Furunculosis
• Treatment of acute lesions – ABX may arrest early furuncles.
– Incision and drainage AFTER furuncle is localized with definite fluctuation. • No incision of EAC or nasal furuncles. TX with ABX.
– Upper lip and nose ,‘danger triangle’, requires prompt treatment with ABX to avoid possible venous sinus thrombosis, septicemia, meningitis.
12 Treatment of Chronic Furunculosis Avoid auto-inoculation, Eliminate carrier state.
– Nares, axilla, groin and perianal sites of colonization.
– Use Anti-staph cleansers – soap, chlorhexidine.
– Frequent laundering
– Bactroban to nares of pt and family members • BID to nares for one week (q 4th week.).
– Rifampin 600mg QD for 10 days with cloxacillin 500 mg QID (or Clindamycin 150mg qd for 3 mo)
13 Pyogenic Paronychia
• Presentation: Tender painful swelling involving the skin surrounding the fingernail. • Etiology: Moisture induced separation of eponychium from nail plate by trauma or moisture leading to secondary infection. – Often work related • Bacteria cause acute abscess formation, Candida causes chronic swelling. • Treatment: • Avoid maceration / trauma • I&D of abscess • PCN, 1st Gen Cephalosporin, augmentin. • Chronic infection requires fungicide and a bactericide.
14 Pyogenic Paronychia
•
15 Pyogenic Paronychia
16 Other predominately Staph Infections. • Botrymycosis – Presentation: Chronic, indolent d/o characterized by nodular, crusted, purulent lesions. • Sinus tracts discharge sulfur granules. Scaring. – Uncommon disorder. Altered immune function. – S. Aureus most common. (Pseudo, E-coli, Proteus, Bacteroides, Strep.)
• Pyomyositis – S. aureus abcess in deep, large striated muscle. – Most frequent location is thigh – Occurs in tropics and in children as well as AIDS pts. – Not associated with previous laceration.
17 Pyomyositis
•
18 Impetigo Contagiosa
• Presentation: 2mm erythematous papule develops into vesicles and bullae. Upon rupture a straw colored seropurulent discharge dries to form yellow, friable crust. • Etiology: S. Aureus > S. Pyogenes. • Lesions located on exposed parts of body. • Group A Strep can cause AGN – Children <6 yrs old. – 2% to 5% – Serotytpes 49, 55, 57, 60 strain M2 most associated – Good prognosis in children.
19 Impetigo Contagiosa
• Treatment – PCN, 1st Gen. Cephalosporin. – Topical: bacitracin or mupirocin after soaking off crust. • Topical ABX prophylaxis of traumatic injury. – Reduced infection 47 % • Treatment of nares for carriers.
20 Impetigo Contagiosa
•
21 Impetigo Contagiosa
22 Impetigo Contagiosa
•
• Presentation: Large, fragile bullae, suggestive of pemphigus. Rupture leaves a circinate, weepy crusted lesion (impetigo circinata). Collarette of scale present.
• Affects newborns at the 4-10th days of life. Adults in warm climates
24 Bullous Impetigo
25 Bullous Impetigo
26 Bullous Impetigo
•
27 Staphylococcal Scalded Skin Syndrome. • Presentation: Febrile, rapidly evolving generalized desquamation of the skin seen primarily in neonates and children. – Begins with skin tenderness and erythema of neck groin, axillae with sparing of palm and soles – Blistering occurs just beneath granular layer. – Positive Nikolsky’s sign
• Etiology: Exotoxin from S. Aureus infection located at a mucosal surface..
• Differentiate from TENS by location of blister plane high in epidermis. • Treatment as before. Prognosis is good. 28
Staphylococcal Scalded Skin Syndrome •
29 Staphylococcal Scalded Skin Syndrome
• Acute, febrile, multisystem disease. – One diagnostic criteria is widespread maculopapular eruption. • Causes: – S. Aureus : cervical mucosa historically in early 1980’s. Also: wounds, catheters, nasal packing. Mortality 12 %. – Group A Strep : necrotizing fasciitis. Mortality 30%. • Diagnosis: CDC – Temp >38.9C, erythematous eruption with desquamation of palms and soles 1-2 wks after onset. Hypotension – AND involvement of three of more other systems • GI, muscular, renal, CNS. – AND Test for RMSF, Leptospirosis and rubeola as well as blood urine and CSF should be negative.
31 Toxic Shock Syndrome
• Treatment: – Systemic ABX, – Fluid therapy – Drainage of S. Aureus infected site.
32 Streptococcal Skin Infections
33 Ecthyma
• Presentation: Vesicle/pustule which enlarges over several days and becomes thickly crusted. When crust is removed a superficial saucer shaped ulcer remains with elevated edges. – Nearly always on shins or dorsal feet. – Heals in a few weeks with scarring. • Agent: Staph or Strep. • Heal with scaring • Gangrene in predisposed individuals. • Treatment: Clean, topical and systemic ABX.
34 Ecthyma
•
• Presentation: 24 –48 hrs after Strep. Pharyngitis onset. – Cutaneous: • Widespread erythema with 1-2 mm papules. Begins on neck and spreads to trunk then extremities. • Pastia’s lines – accentuation over skin folds with petechia. • Circumoral pallor • Desquamation of palms and soles at appox two wks. – May be only evidence of disease. – Other: strawberry tongue • Causes: erythrogenic exotoxin of group A Strep. • Culture to recover organism or use streptolysin O titer if testing is late. • TX: PCN, E-mycin, Cloxacillin.
36 Scarlet Fever
37 Scarlet Fever
38 Scarlet Fever
39 Scarlet Fever
40 Erysipelas
• Presentation: erythematous patch with a distinctive raised, indurated advancing border. Affected skin is very painful and is warm to touch. Freq. associated with fever , HA and leukocytosis >20,000. – Face and Legs are most common sites. – Involves superficial dermal lymphatics • Cause: Group A strep., (Group B in newborns) • Differential: – Contact derm: more itching little pain. – Scarlet fever: widespread punctate erythema – Malar rash of Lupus and Acute tuberculoid Leprosy: Absence of fever pain and leukocytosis. • Treatment: Systemic PCN for 10 days.
41 Erysipelas
42 Erysipelas
43 Erysipelas
44 Cellulitis
• Presentation: Local erythema and tenderness which intensifies and spreads. Often associated with a discernable wound. Lymphangitis, fever and streaking may accompany the infection. • Group A strep and S. Aureus are usually causative. • Gangrene and sepsis possible particularly in compromised pt. • Treatment: PCNase – resistant PCN, 1st Gen Ceph.
45 Cellulitis
46 Cellulitis
47 Necrotizing Fasciitis • Presentation: Following surgery or trauma (24 to 48 hours) - erythema, pain and edema which quickly progress to central patches of dusky blue discoloration. Anesthesia of the involved skin is very characteristic. By day 4-5 the involved area becomes gangrenous. • Infection of the fascia. • Many causative agents. Aerobic and anaerobic cultures should be taken. • Treatment: Early debridement. ABX. • 20% mortality in best cases • Poor prognostic factors: Age >50, DM, Atherosclerosis, involvement of trunk, delay of surgery >7 days.
48 More Staph and Strep Infections
• Blistering Distal dactylitis – Superficial blisters on volar fat pads – Typical pt is 2-16 yrs old • Perianal Dermatitis – Superficial, perianal, well demarcated rim of erythema which is often confused with a dermatitis. – Typical pt is 1-8 yrs old. • Group B infection – Consider in any neonates. Also seen in adults with DM and peripheral vascular disease. • Staph Iniae – 1997 first reported – Cellulitis of hands assoc with preparation of tilapia fish.
49 Perianal Dermatitis
50 Other Gram Positive Infections.
51 Erysipeloid of Rosenbach. • Presentation: Purple, often polygonal, sharply marginated patches occurring on the hands. The central portion of the lesion may fade as the border advances. New purplish patches appear at nearby sites ( or possibly distant sites).
• Causative agent: Erysipelothrix Rhusopathiae. Rod shaped grm (+) that forms long branching filaments. Culture on media fortified with serum at room temp.
• Organism found on dead animal matter and the affliction is seen most commonly among fishermen, veterinarians, and in the meat packing industry (esp pork)
• Treatment: PCN 1.0 gm/day 5-10 days.
52 Erysipeloid
53 Anthrax
Three forms: – Cutaneous 95% of cases. – Inhalation – GI • Cutaneous presentation: Inflammatory papule rapidly becomes a bulla surrounded by intense erythema which spontaneously ruptures purulent or sanguineous contents. A dark brown eschar surrounded by vesicles then develops with induration. Regional lymph glands then enlarge and frequently suppurate. The lesion is not tender or painful. – Mild cases - gangrenous skin sloughs and eschar heals. – In severe cases erythema and extensive edema develops. Lesions appear at other sites. Fever, prostration and death (20% of untreated cases.)
54 Anthrax
• Human infection generally from infected animals. Human to human transmission is possible. • Diagnosis: smear with gram stain and cultures of wound. – Gamma bacteriophage to identify – Mice serum titer. – Electrophoretic immunoblots. • Treatment: PCN G 2 million units IV q 6 hours for 4-6 days followed by oral PCN for 7-10 days.
55 Anthrax
56 Anthrax
57 Anthrax
58 Anthrax
59 Anthrax
60 Listeriosis
• Listeria Monocytogenes • Ubiquitous organism which usually causes meningitis of encephalitis. • Rare cutaneous affliction causing erythematous, tender papules and pustules with lymphadenopathy, fever and malaise. • Risk to immunosuppressed – Neonates: Granulomatosis infanta peptica. • May be missed on bacteriologic exam. Serologic test useful. • Treatment: sensitive to most ABX.
61 Cutaneous Diphtheria
• Corynebacterium Diphtheriae infection in unimmunized individual • Presentation: – Ulcer with a hard rolled border with a pale blue tinge. A leathery gray membrane often coves the lesion. – Eczematous, impetinginous, vesicular or pustular scratches. • Paralysis and cardiac complication from Diphtheria toxin are possible. • Common in tropical areas with most U.S. cases from unimmunized migrant workers. • Treatment: Diphtheria antitoxin, E-mycin is DOC. Also rifampin and PCN.
62 Desert Sore
• Ulcerative disease endemic amongst bushmen and soldiers in Australia. • Presentaion: Grouped vesicles on extremities which rupture to form superficial, indolent ulcers that may be 2.0 cm in diameter. • Cause: Staph, Strep and Corynebacterium Diphtheria. • Treatment: Diphtheria antitoxin if organism present and topical ABX with oral PCN or E- mycin.
• Presentation: – Inflammatory papule with vesiculation and ulcer formation frequently with undermined edges. – Pseudomembrane may be present or simply crusting. – Minimal distress other then mild itching. – Autoinnouculation – Usually single lesion on one extremity. • Most common in native laborers or school children during the ‘rainy season’. • Usually occur at sites of cutaneous injury.
64
Tropical Ulcer
• Etiology: Many organisms found under description of ‘topical ulcer’: – Bacteriodes Fusiformis, spirochetes, anaerobes. • Differential: – Vascular ulcers • Arteriosclerotic ulcer – deep to expose fascia and tendons. • HTN ischemic ulcer – shallow, painful mid to lower legs. • Venous ulcers – shallow, varicosities. Above medial malleolus. – Other: • Desert ulcer – C diptheriae • Gummatous ulcer – punched out, other syphilis signs. • Tuberculous ulcer – not usually on leg. • Mycotic ulcer – nodular with fungi on inspection. • Buruli ulcer – Mycobacterium ulcerans. • Leshmania ulcer – contans Leishmania tropicans, not on leg. • Ulcer of blood abnormalities. 65 Tropical Ulcer
66 Tropical Ulcer
67 Erythrasma
• Presentation: sharply delineated, dry, brown, slightly scaling patches located in intertrignous areas esp the axillae, genitocrural crease and webs of 4-5 toes. Rarely, widespread lesions will occur with lamellated plaques. • Lesion are generally asymtomatic except for the groin where minor itching may be reported. • Extensive involvement is associated with DM and other debilitating disease. • Etiology: Corynebacterium Minutissimum. • Diagnosis: Woods lamp – coral red. • Treatment: e-mycin 250 qid x 7 days. Tolnaftate, miconazole, e-mycin, clindamycin topicals also effective.
68 Erythrasma
69 Erythrasma
70 Intertrigo
• Presentation: Superficial inflammatory dermatitis where two skin surfaces are in apposition. • Etiology: Friction and moisture allows infection by bacteria (Staph, Strep, Pseudo.) or fungi or both.
71 Intertrigo
72 Intertrigo
73 Intertrigo
• Presentation: Thick weight bearing portions of the soles gradually covered by asymtomatic round pits 1-3 mm in diameter. Pits may become confluent forming furrows. Rarely, palms may be affected. • Etiology: unknown. Micrococcus sedentarius in synergy with corynebacteria is suspected • Men with sweaty feet are most susceptible. • Treatment: Topical E-mycin, clindamycin. Miconazole, benzoyl perioxide gel, AlCl solution.
75 Pitted Keratolysis
76 Pitted Keratolysis
77 Gas Gangrene
• Presentation: Several hours after a patient receives a deep laceration, severe pain and wound site crepitance develop as well as fever, chills and prostration. A mousy odor is characteristic. • Etiology: (2 types) – Clostridium types: perfringens, oedematiens, septicum and haemolyticum. Acute onset ! – Peptostreptococcus. Delayed onset up to several days. • Treatment: – Clostridium: Wide debridement and PCN G, hyperbaric – Peptostreptococcus: Surgical debridement limited to glossy necrotic muscle.
78
Gas Gangrene
79 Chronic Undermining Burrowing Ulcers ( Meleney’s Gangrene) • Presentation: Pt who recently (1-2 wks) underwent surgical drainage of a peritoneal or lung abscess develops carbunculoid appearance at the sutures or wound site. The lesion then differentiates into three zones: outer zone- bright red, middle zone-dusky purple, inner zone- gangrenous with central areas of granulation tissue. Pain is excruciating. • Etiology: Peptostreptococcus in periphery. S. Aureus or Enterobacteriaceae in zone of gangrene. – Bacterial synergetic gangrene • Differential: gangrenous ecthyma (pseudomonas), amebic (liver abscess associated), Pyoderma gangrenosa (no bacteria) • Treatment: Wide excision with ABX (PCN and aminoglycoside). 80
Fournier’s Gangrene of the Penis and Scrotum • Presentation: Gangrenous infection of penis, scrotum or perineum which spreads along fascial planes. • Etiology: Group A Strep or mixed organism. • Ages 20-50 • Culture for aerobic and anaerobic organisms. • Treatment: ABX as indicated.
81