Abscess
Definition
A.An abscess is a pocket of pus under the skin tissue that may invade deeper skin tissue.
Pathogenesis
A.An abscess develops when a collection of bacteria builds up in the tissue of the body. There may be several types of bacteria present. One common organism is methicillin-resistant Staphylococcus aureus.
Common Complaints
A.Painful, swollen, erythemic pocket of pus under the skin tissue
Subjective Data
A.Ask the patient when signs and symptoms of infection, discomfort, redness, or swelling began.
B.Has the patient experienced fever, chills, or other symptoms?
C.What has been used to treat the abscess? Has heat, ice, topical antibiotics, lotions, and so on, been used?
D.What treatments make the symptoms worse or better?
Physical Examination
A.Assess site of abscess.
B.Measure length times width.
C.Note erythema, edema, warmth/fever of tissue, tenderness with palpation. Does pain radiate to other areas? If so, where?
D.Is abscess open and draining fluid? If so, note color, consistency, and odor of drainage.
Diagnostic Tests
A.Laboratory testing (complete blood count [CBC], comprehensive metabolic panel [CMP]).
B.Open or draining abscess: Culture and sensitivity, and Gram stain.
Differential Diagnoses
A.Wound abscess.
B.Cellulitis.
C.Folliculitis.
D.Pilonidal cyst.
E.Pressure injury.
F.Necrotizing fasciitis.
G.Gas gangrene.
H.Acute gout.
Plan
A.General interventions:
1.Incision and drainage (I&D) can successfully be performed for an uncomplicated abscess.
2.Precautions should be considered for contraindications for an I&D. These contraindications include the following:
a.Abscess location (perirectal, neck, hand, central area of the face, breasts, and in close proximity to major nerves and blood vessels).
b.Recurrent abscesses.
3.After completing the I&D, the area should be allowed to close by secondary intention.
4.Sterile packing should be inserted into the cavity for abscesses larger than 5 cm in diameter and for patients with compromised immune systems.
B.Patient teaching:
1.Educate the patient regarding home care for the site of the abscess. If packing is required, instruct patient to return to the physician’s office for packing, or consider home healthcare to perform dressing changes.
2.New packing should be replaced every 24 to 48 hours until drainage has resolved and until new granulation tissue is present.
3.Once packing is no longer necessary, the patient will clean the cavity with warm, wet compresses two to three times a day until healed.
C.Pharmaceutical therapy:
1.Oral antibiotic treatments: Antibiotics should be prescribed; use antibiotics that are sensitive to methicillin-resistant S. aureus (MRSA). See pharmacological treatment options in this chapter under the section Cellulitis.
Follow-Up
A.The patient should return in 24 to 48 hours to evaluate the cavity and insert new packing as needed.
B.If symptoms worsen prior to follow-up, recommend that the patient to proceed to the ED for further assessment.
Consultation/Referral
A.Consult with physician for all abscesses requiring I&D with packing.
B.Consult physician for all abscesses that are not responding to antibiotic treatment for further evaluation.
C.See the section Cellulitis
for other treatment options.
Cellulitis
Definition
A.Cellulitis is an acute inflammation and infection of the skin and subcutaneous tissue.
Incidence
A.Cellulitis is not a reportable infection; therefore, the exact incidence is not known. However, some studies show that the incidence of cellulitis is approximately 200 patients per 100,000 patient years.
Pathogenesis
A.Cellulitis occurs when bacteria attack the skin tissue, which involves the dermis and subcutaneous tissue. The most common organisms causing this bacterial infection include beta-hemolytic streptococci (groups A, B, C, G, and F) and S. aureus.
B.The most common organisms causing an abscess include S. aureus (either methicillin-susceptible S. aureus or MRSA) that occurs in up to 75% of cases, and Group A streptococci.
C.Bacteria may invade healthy tissue but commonly occurs in damaged tissue where there is a break in the skin, allowing invasion of the tissue that can lead to bacterial infection.
Predisposing Factors
A.Age (adults older than 45 years, geriatrics).
B.Immunocompromised immune system.
C.Chronic medical conditions (diabetes).
D.History of intravenous (IV) drug abuse.
E.Alcoholism.
F.Peripheral vascular disease.
G.Previous history of cellulitis.
Common Complaints
A.Erythema, pain, swelling, and warmth are the classic symptoms.
B.Fever, malaise, and chills.
C.Lymphadenopathy of lymph nodes adjacent to site of infection.
D.Trauma to skin tissue.
Other Signs and Symptoms
A.Drainage/discharge at wound site.
B.Erythemic streaks that progress away from the infection site.
C.Systemic signs of infection (fever, tachycardia, tachypnea, hypotension, change in mental status).
Potential Complications
A.Sepsis.
B.Necrosis of tissue.
C.Osteomyelitis.
Subjective Data
A.Ask the patient if there was any activity/injury that preceded the episode.
B.Inquire regarding the onset, location, and duration of pain and symptoms. Has the area increased in size or spread to other areas?
C.Ask the patient to describe pain, for example, crushing, stabbing, or burning sensation.
D.Have the patient rate pain on a scale of 0 to 10, with 0 being no pain.
E.Inquire regarding any previous trauma to affected area. Has anyone else had similar symptoms?
Physical Examination
A.Vital signs: Check temperature, pulse, respirations, and blood pressure.
B.Inspect:
1.Inspect general appearance of skin. Note location of involved skin and note erythemic streaking if present.
2.Measure size (mm/cm) of skin involvement. May include pictures if applicable. Outline the erythema with a marker for ease of assessment between medical professionals as well as patient if being discharged for home monitoring.
3.Note presence of erythema, edema, and color of skin tissue involved (pink, erythemic, necrotic, pale, etc.).
C.Palpate:
1.Palpate site for warmth, tenderness, firmness, and fluctuance.
2.Palpate adjacent lymph nodes to assess for lymphadenopathy.
D.Auscultate:
1.Heart.
2.Lungs.
Diagnostic Tests
A.Laboratory (blood cultures, Gram stain, culture specimen from the abscess, CBC with diff, C-reactive protein [CRP] creatinine, bicarbonate, creatine phosphokinase):
1.Blood cultures: Recommended for patients presenting with signs of systemic toxicity, extensive skin involvement, a history of comorbid conditions, history of recurrent cellulitis, and/or trauma (dog/cat bite, puncture wounds, etc.).
2.Culture and sensitivities should be performed on patients with signs of systemic infection, severe skin impairment, history of chronic conditions, recurrent infections, and a history of animal or water injury.
B.Imaging studies:
1.Ultrasound to assess for abscess.
2.X-ray may be performed if suspicious for osteomyelitis.
3.CT or MRI may be considered when assessing for necrotizing fasciitis.
Differential Diagnosis
A.Cellulitis.
B.Abscess.
C.Dermatitis.
D.Erysipelas. (A superficial skin infection that commonly occurs on the face, ears, and/or lower legs. It commonly presents with erythema of the skin with a distinct demarcated border commonly caused by group A streptococcus bacteria. Erysipelas is more commonly seen in older adults.)
Plan
A.General interventions:
1.If there are signs of systemic infection, hospitalization is required.
2.Educate the patient regarding care for site.
3.Instruct patient on reporting worsening symptoms as soon as possible to prevent sepsis.
B.Patient teaching:
1.Instruct patient to keep site clean and dry, recommending elevation of extremity if applicable.
2.Recommend over-the-counter (OTC) pain medication such as acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) as needed for pain.
3.Advise patient to notify the primary provider for the following symptoms:
a.Fever more than 100.0°F.
b.Chills.
c.Increase in size of redness or change in size/consistency of site (i.e., abscess formation).
d.Erythemic streaks.
e.Lymphadenopathy.
f.Increase in pain.
4.Instruct the patient on use of antibiotics and stress the importance of finishing the full course of prescribed antibiotics.
5.Once the infection has resolved, stress the importance of notifying the primary provider for reoccurring symptoms.
6.Recurrent cellulitis should be evaluated for the cause. Chronic underlying conditions, such as edema, should be treated to prevent future episodes. Edema may be treated with compression stocking therapy and/or the use of diuretics.
C.Pharmaceutical therapy:
1.Uncomplicated cellulitis: Oral treatments—cephalexin 500 mg tablet every 6 hours; or dicloxacillin 500 mg tablet every 6 hours; or clindamycin 300 to 450 mg tablet every 6 to 8 hours. Oral medications are prescribed for 5 to 10 days:
a.Empiric treatment for MRSA should be considered for the following patients:
i.Patients who do not respond to initial treatment.
ii.Patients with signs of sepsis.
iii.Patients who have recurrent cellulitis.
iv.Patients who have a history of MRSA.
2.Cellulitis MRSA: Oral treatments—doxycycline 100 mg tablet twice a day or clindamycin 300 to 450 mg tablet three times a day or Trimethoprim/sulfamethoxazole (TMPSMX) double strength (DS) tablet twice a day or minocycline 200 mg tablet once then 100 mg tablet twice a day or linezolid 600 mg tablet twice a day or tedizolid 200 mg tablet daily. Oral medications are prescribed for 5 to 10 days:
a.Dosing should be individualized according to the underlying conditions. Obese patients may have a higher failure rate if not prescribed adequate dosing.
b.Patients with purulent drainage should be treated for MRSA pending culture results.
c.Patients with renal impairment will require dosage adjustments.
3.Complicated cellulitis: IV antibiotics should be prescribed for patients with complicated cellulitis and/or erysipelas with signs of sepsis (fever/chills). Antibiotic treatments may include cefazolin, oxacillin, nafcillin, vancomycin, daptomycin, and ceftaroline.
Follow-Up
A.Patient needs to follow up in 24 to 48 hours for reassessment.
B.If worsening symptoms are present, recommend that the patient proceed to the ED for evaluation and treatment.
Consultation/Referral
A.If necrotizing fasciitis is suspected, referral for a surgical consult is imperative.
B.Inpatient hospitalization is recommended for the following: