1. Inpatient Skin and Soft Tissue Infections Keri Holmes-Maybank, MD Medical University of South Carolina September, 2012

2. Objectives • Identify appropriate empiric antibiotics for treatment of SSTI’s. • Identify appropriate antibiotics for deescalation of SSTI treatment. • Recognize patients appropriate for inpatient hospitalization of SSTI’s. • Recognize appropriate use of blood cultures, needle aspiration and punch biopsies in SSTI’s.

3. Key Messages • Blood culture for skin and soft tissue infections are extremely low yield, approximately 5%. • Consider hospitalization for patients with systemic signs of illness. • MRSA infections have led to an increase in skin and soft tissue infections. • Using guidelines for skin and soft tissue infections leads to a decrease in the emergence of antibiotic resistance.

4. SSTI’s • Increasing ER visits and hospitalizations • 29% increase in admissions, 2000 to 2004 • Primarily in age <65 • Presume secondary to community MRSA • 50% cellulitis and cutaneous abscesses • Estimated $10 billion SSTI 2010

5. IDSA Guidelines • “Practice guidelines are systematically developed statements to assist practitioners and patients in making decisions about appropriate health care for specific clinical circumstances.”

6. Guidelines • Reduce emergence of resistant organisms • Reduce hospital days • Reduce costs: • Blood cultures • Consultations • Imaging • Hospital days • 2011-Implementation of treatment guidelines • Decreased use of blood cx • Decreased advanced imaging • Decreased consultations • Shorter durations of therapy • Decreased use of anti-pseudomonal • Decreased use of broader spectrum abx • No change in adverse outcomes • Decreased costs

7. Inpatient Hospitalization • Systemic illness • HR >100 and • Temp >38oC or <36oC and • Systolic bp <90 or decrease of 20 mmHg < baseline • Hypotension and • CRP>13 • Marked left shift • Elevated creatinine • Low serum bicarbonate • CPK 2 x the upper limit of normal

8. Inpatient Hospitalization • Rapid progression of cellulitis • Worsening infection despite appropriate antibiotics • Tissue necrosis • Severe pain • Altered mental status • Respiratory, renal or hepatic failure • Co-morbidities:  immune compromise, neutropenia, asplenia, preexisting edema, cirrhosis, cardiac failure, renal insufficiency

9. Obtain Careful History • Immune status • Geographic locale • Travel history • Recent trauma or surgery • Previous antimicrobial therapy • Lifestyle - occupation • Hobbies • Animal exposure • Bite exposure

10. Testing • Blood cultures positive <5% • Needle aspiration 5-40% • Punch biopsy 20-30%

11. Blood Cultures • HR >100 , Temp >38oC and <36oC, Sys <90mmHg • Lymphedema • Immune compromise/neutropenia/malignancy • Pain out of proportion to exam • Infected mouth or eyes • Unresponsive to initial antibiotics • Water-associated cellulitis • Diabetes • Recurrent or persistent cellulitis • Concern for a cluster or outbreak

12. Needle Aspiration or Skin Biopsy • HR >100 , Temp >38oC and <36oC, Sys<90mmHg • Hypotension and • CRP>13 Marked left shift • Elevated creatinine Low serum bicarb • CPK 2 x upper limit of normal • Immune compromise/neutropenia/malignancy • Diabetes • Animal or human bite wounds

13. SSTI • Indicators of more severe disease: • Low sodium • Low bicarb • High creatinine • New anemia • Low or high wbc • High CRP (associated with longer hospitalization)

14. Empiric Anti-MRSA Antibiotics • Recent hospitalization • Residence in long term care facility • Recent antibiotic treatment • HIV • Men who have sex with men • Injection drug use • Hemodialysis • Incarceration • Military service • Sharing needles, razors, sports equipment • Diabetes

15. Deescalation • Acute skin findings resolving • Afebrile • No signs of systemic illness • Should see systemic signs improvement by 48 hours • Should see skin improvement 3-5 days by at the latest

16. Broaden Antibiotics • If no improvement in systemic signs in 48 hours • If no improvement in skin in 72 hours • As antibiotics kill organisms, toxins released may cause a worsening of skin findings in first 48 hours

17. Cellulitis • 65% relative increase since 1999 • 600,000 admissions annually

18. Risk Factors for Cellulitis • Obesity • Edema • Venous insufficiency • Lymphatic obstruction • Fissured toe webs • Maceration • Fungal infection • Inflammatory dermatoses – eczema • Repeated cellulitis • Subcutaneous injection or illegal drugs • Previous cutaneous damage • All lead to breaches in the skin for organism invasion

19. Surgical Risk Factors • Saphenousvenectomy • Axillary node dissection for breast cancer • Gyn malignancy surgery with lymph node dissection *** in conjuction with XRT • Liposuction

20. Non-Purulent Cellulitis • No purulent drainage, no exudate, no associated abscess • beta hemolytic streptococci • Antibiotics: • Nafcillin • Cefazolin • Ceftriaxone • Clindamycin • Vancomycin • Modify to MRSA coverage if • No improvement in skin findings within 72 hours • Signs of severe systemic illness

21. Non-Purulent Cellulitis • Deescalation: •  Penicillin • Amoxicillin • Amoxicillin/clavulanate • Cephalexin • Treatment duration: • Discontinue abx 3 days after acute inflammation disappears • Usually 5-10 days of treatment

22. Purulent/Complicated Cellulitis • Purulent drainage • Exudate • Absence of a drainable abscess • Deeper tissue - surgical/traumatic wound infection, major abscess, infected ulcer or burn

23. Purulent/Complicated Cellulitis • MRSA coverage • Antibiotics: • Vancomycin • Clindamycin • Linezolid (restricted to ID) • Daptomycin (restricted to ID)

24. Purulent/Complicated Cellulitis • Deescalation: • Clindamycin • Trimethoprim/sulfamethoxazole • Linezolid (restricted to ID) • Treatment duration: • Discontinue abx 3 days after acute inflammation disappears • Usually 5-10 days of treatment

25. Secondary Treatment of Cellulitis • Elevation of affected leg • Compression stockings • Treat underlying tineapedis, eczema, trauma • Keep skin well hydrated

26. Confused with Cellulitis • Acute dermatitis • Gout • Herpes zoster • Lipodermatosclerosis • Deep vein thrombosis • Contact dermatitis • Drug reaction • Foreign body reaction • Herpes zoster

27. Abscess

28. Abscess • ALWAYS, ALWAYS • Incision and drainage • Culture aspirate

29. Abscess –When to Add Antibiotics • Multiple sites of infection • Rapid progression in presence of cellulitis • Systemic illness (fever, hypotension, tachycardia) • Immune compromise • Elderly • Difficult to drain area (hand, face, genitalia) • Lack of response to incision and drainage • Septic phlebitis - multiple lesions • Gangrene

30. Abscess Antibiotic Coverage • MRSA coverage:cellulitis, severe disease, rapid progression, septic phlebitis, constitutional symptoms, difficult to drain • Antibiotics: • Vancomycin • Clindamycin • Daptomycin (restricted to ID) • Linezolid (restricted to ID) • c-MRSA or beta hemolytic streptococci • Antibiotics • Clindamycin • Trimethoprim/sulfamethoxazole + beta lactam • Doxycycline + beta lactam

31. Abscess • Deescalation: • Clindamycin • Trimethoprim/sulfamethoxazole • Linezolid (restricted to ID) • Treatment duration: • Discontinue abx 3 days after acute inflammation disappears • Usually 5-10 days of treatment

32. Animal Bites

33. Animal Bites • Pasteurella – mc organism • Antibiotics: • Ampicillin/sulbactam • Piperacillin/tazobactan • Cefoxitin • Meropenem • Ertapenem (restricted to ID and Surgery) • Tetanus toxoid (if not up to date)

34. Animal Bites • Deescalation • Amoxicillin/clavulanate • Doxycycline • Treatment duration: • Discontinue abx 3 days after acute inflammation disappears • Usually 5-10 days of treatment

35. Human Bites

36. Human Bite • Antibiotics: • Ampicillin/sulbactam • Meropenem • Ertapenem (restricted to ID and Surgery) • Tetanus toxoid (if not up to date) • Closed fist*** • Antibiotics: • Cefoxitin • Ampicillin/sulbactam • Ertapenem(restricted to ID and Surgery) • Tetanus toxoid (if not up to date) • Hand surgery consult***

37. Human Bites • Deescalation: • Amoxicillin/clavulanate • Moxifloxacin + clindamycin • Trimethoprim/sulfamethoxazole + metronidazole • Treatment duration: • Discontinue abx 3 days after acute inflammation disappears • Usually 5-10 days of treatment if no joint or tendon involvement

38. Surgical Site Infection

39. Surgical Site Infection • Pain, swelling, erythema, purulent drainage • Usually have no clinical manifestations for at least 5 days after operation • Most resolve without antibiotics • Open all incisions that appear infected >48 hours after surgery • No antibiotics if temperature <38.5oC and HR <100 bpm

40. Surgical Site Infection • If temperature >38.5oC or HR >100 bpm: • Trunk, head, neck, extremity • Cefazolin • Clindamycin • Vancomycin if MRSA is suspected • Perineum, gi tract, female gu tract • Cefotetan • Ampicillin/sulbactam • Ceftriaxone + metronidazole or clindamycin • Fluoroquinolone + clindamycin • Treatment duration: • Usually 24-48 hours or for 3 days after acute inflammation resolves

41. Neutropenia and SSTI’s

42. Neutropenic Patients with SSTI • ALWAYS blood CULTURES • Initial infection - <7 days neutropenia • Antibiotics • Carbapenems • Cefepime • Ceftazidine • Piperacillin/tazobactam PLUS • Vancomycin • Linezolid (restricted to ID) • Daptomycin (restricted to ID) • (discontinue if culture negative after 72-96 hours)  

43. Neutropenic Patients with SSTI • Subsequent infection- >7days neutropenia (fungi, viruses, atypical bacteria) • Treatment: • Amphotericin B • Micafungin (may require higher dose and ID consult) • Voriconazole (restricted to ID, Heme/Onc, Critical Care, Pulmonary, and Transplant) PLUS • Carbapenems • Cefepime • Ceftazidine • Piperacillin/tazobactam PLUS • Vancomycin • Linezolid (restricted to ID) • Daptomycin (restricted to ID) • (discontinue if culture negative after 72-96 hours)

44. Neutropenic Patients with SSTI • Deescalation: • Ciprofloxacin and amoxicillin/clavulanate • Treatment duration: • At least 7 days

45. Vascular-Access Devices in Neutropenia • Device predisposes to SSTI • 66% Gram positive • Entry site infection • Antibiotics • Tunnel infection and vascular port-pocket infection • Device removal and antibiotics

46. Diabetic Foot Ulcers

47. Infected Diabetic Foot Ulcers • Not all diabetic foot ulcers are infected. • Indications of infection: • Purulent secretions OR • 2 of manifestations of inflammation: • Redness • Warmth • Swelling/induration • Pain/tenderness

48. Diabetic Foot Ulcers • Common, complex, costly • Largest number of diabetes related hospital bed days • Most common proximate, non-traumatic cause of amputations

49. Diabetic Foot Ulcers • Always obtain specimen (biopsy, ulcer curettage, aspiration) and treat with antibiotics and wound care • Mild ulcer • Cellulitis or erythema extends <2cm around ulcer, infection limited to skin • Antibiotics: • Clindamycin • Cephalexin • Amoxicillin/clavulanate • Trimethoprim/sulfamethoxazole • Treatment duration • Usually 1-2 weeks treatment

50. Diabetic Foot Ulcers • Moderate or Severe ulcer • Cellulitis or erythema extends >2cm around ulcer, fever, ams, hypotension, leukocytosis, acidosis, severe hyperglycemia • Antibiotics: • Vancomycin and ceftazidime • (consider adding metronidazole, piperacillin/tazobactam, meropenem) • Deescalation: • Moxifloxacin • Amoxicillin/clavulanate • Trimethoprim/sulfamethoxazole • Treatment duration: • Usually 2-4 weeks of treatment