Cellulitis is a quick spreading infection caused by bacteria that enters the skin and subcutaneous structures resulting in severe inflammation that invades superficial tissue (Goodman & Fuller, 2009). In adults the bacteria that usually causes cellulitis is either streptococcus pyogenes or staphylococcus and in children the bacteria is commonly haemophilus
influenza type b, other types of bacteria can cause cellulitis but is not as common (Goodman & Fuller, 2009). Patients at high risk for cellulitis include older adults and individuals with diabetes, malnutrition, steroid medication, and existing wounds (Goodman & Fuller, 2009). Anyone can acquire cellulitis because all of us have bacteria on our skin and under our nails that could enter with a scratch or scrap of the skin. Frequent hand washing is the best way to avoid getting cellulitis, the Center for Disease Control and Prevention (CDC) strongly recommend washing your hands for 20 seconds while humming the happy birthday song twice (CDC Features – Wash Your Hands, 2014). Hand washing is recommended after food preparation, blowing your nose, coughing, toileting, touching trash or pets, changing diapers, touching dressing or sores, before eating and preparing food (CDC Features – Wash Your Hands, 2014). Many times patients with lower extremity edema resemble cellulitis as a result of medication induced sodium overload and can add to the clinician’s confusion (Simon, 2014).

Cellulitis typically affects the soft fatty tissue and skin, but can invade the deep tissue around the muscle causing skin erythema, edema, blisters, tenderness to touch and severe weight bearing pain, and occasionally nodular firmness (Goodman & Fuller, 2009). I frequently describe cellulitis to my patients as a soft tissue infection that resembles a severe sunburn occurring from the inside out. Cellulitis presents as blotches of red skin that is hot and painful with defined borders and frequently cause red lines stretching out from the blotches that signify infected lymph structures (Goodman & Fuller, 2009). In addition, odor within the wound of cellulitis is not apparent because the exudate is serous thin (clear or yellow) drainage not purulent thick (green or yellow) drainage. Epidemiology of cellulitis has a rate of 24.6 per 1000 persons affecting males more than females and patients between 45 and 65 years old with the most common infected site being the lower extremity (Ellis et al. 2006). My role in cellulitis is recognizing the clinical signs, to avoid misdiagnosis and to provide appropriate intervention using topical medication and debridement. Additional interventions include: extremity elevation, topical medication such as Silvadene, gel cool packs, dressing to absorb exudate and if necessary debridement (Nazarko, 2008). Patients will complain of sudden fever or flu symptoms, severe pain in the affected area, redness and swelling that spreads quickly (PubMed Health, 2013; Nazarko, 2008). Cellulitis is frequently misdiagnosed by as much as 1/3 of the time because the symptoms are confused with venous eczema, oedema with blisters, venous insufficiency ulcers, deep venous thrombosis (DVT), thrombophlebitis, liposclerosis, and vasculitis (Nazarko, 2008).

Cellulitis is diagnosed using clinical features of a sudden onset of a red distinct area that is hot, swollen with or without blisters and extremely painful to touch and walk on along with accurate patient history (Nazarko, 2012). Upon patient exam the reddened area is outlined with a permanent marker to observe progression of infection or improvement followed by consistent observation (Nazarko, 2012). In most cases of cellulitis there will be presence of a lesion, cut or fissure that indicates bacteria entry with systemic symptoms of inflammation (Simon, 2014). Many individuals will go to urgent care facilities for cellulitis that is why a classification system was developed for clinicians to use to categorize for timely intervention (Nazarko, 2008; Nazarko 2012). This system uses 4 classes to help providers identify interventional strategies including: class one is patients that have no poisonousness systemic symptoms who respond to oral antibiotics, class two are patients who feel either healthy or ill, but have predisposing factors such as peripheral vascular disease, chronic venous insufficiency, or extremely obese affecting healing require intravenous out-patient antibiotics, class three are individuals feeling ill and have acute sign of confusion, tachycardia, shortness of breath, hypotension, or other causes that may influence healing requiring in-patient antibiotics, class four are patients with septicemia or necrotizing fasciitis requiring in-patient intensive care and antibiotics. (Nazarko, 2008; Nazarko 2012). Evidence-based treatment for cellulitis is oral antibiotics such as cephalosporins for non-problematic cases and doxycycline or co-trimoxazole for stronger bacterial strains (Petrou, 2011). Basic CBC lab test can be used to help in differential diagnosis of cellulitis as well as biopsies to identify whether the invasion is bacterial, viral, fungal, parasitic, or a mycobacterial cause (Petrou, 2011). Complications of cellulitis include: sepsis, osteomyelitis, lymphangitis, endocarditis, meningitis, shock and gaseous gangrene (PubMed Health, 2013). To make cellulitis more complicated for the clinician there is secondary causes of cellulitis that include: surgical dehisced peri wound cellulitis, abscess cellulitis, burn cellulitis, trauma cellulitis and lymphedema cellulitis, but these are not the typical bacterial invading cellulitis but rather the result of a primary cause.

In conclusion, cellulitis is a condition that progresses quickly within approximately 24 hours resulting in defined redness, swelling, blisters, severe superficial inflammation, pain, and flu like symptoms usually with some type of skin lesion, cut or scratch that allows bacteria entry. Timely accurate diagnosis is imperative because delayed and / or inappropriate treatment can cause septicemia, death, unnecessary tissue grafting, increased hospitalization length of stay, re-admissions and outrageous health care cost. Cellulitis requires specific oral or intravenous antibiotics to combat the bacterial infection, pain medication to alleviate pain and interventional wound care is needed to facilitate quick healing and avoid scaring. Cellulitis classification system approach using 4 classes was introduced to health care providers to facilitate out-patient verse in-patient care and to assist in urgency decision and avoid unnecessary hospital admissions. Cellulitis can be confusing for providers because many providers confuse the condition with other similar conditions such as venous eczema, traumatic injury inflammation, oedema with blisters, venous insufficiency ulcers, DVT, thrombophlebitis, liposclerosis, and vasculitis. Unsophisticated lab test such as a CBC can help in diagnosing cellulitis as well as detailed biopsy. Modalities of choice are plain radiography for differential diagnosis initially followed by the inexpensive ultrasound that is extremely accurate and readily available. CT and MRI modality is noninvasive, but are more expensive imaging tests that can identify superficial cellulitis extending to deep tissue anatomy to rule out life threating conditions such as necrotizing fasciitis. Simple frequent hand washing using the 20 second rule is recommended by the CDC to minimize contracting bacterial cellulitis and many other invasive conditions. Cellulitis can be treated with many different topical agents including Silvadene, Bacitracin and Neosporin to sooth the burning inflamed tissue and help in healing progression. It has been my experience that Silvadene topical cream refrigerated is more soothing to cellulitis that Bacitracin or Neosporin.
References
Cellulitis – National Library of Medicine – PubMed Health. (2013, May 15). Retrieved August 6, 2014, from http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001858/.
CDC Features – Wash Your Hands. (n.d.). Retrieved August 8, 2014, from http://www.cdc.gov/Features/HandWashing/
Ellis, S., VanOrman, E. R., Hatch, B. E., Jones, S. S., Gren, L. H., Hegmann, K. T., & Lyon, J. L. (2006). Cellulitis incident in a defined population. Epidemiology Infect, 134(2), 239-299. doi:10.1017/S095026880500484X. Retrieved from Utica College.
Goodman, C. C., & Fuller, K. S. (2009). Pathology implications for the physical therapist (3rd ed.). Missouri: Saunders Elsevier.
Nazarko, L. (2008). Infection control: Cellulitis. Nursing & Residents Care, 10(4), 177-179. Retrieved from Utica College.
Nazarko, L. (2012). An evidence-based approach to diagnosis and management of cellulitis. British Journal of Community Nursing, 17(1), 6-8. Retrieved from Utica College.
Petrou, L. (2011). Cellulitis conundrum. Clinical Dermatology, 35-36. Retrieved from Utica College.
Simon, E. B. (2014). Leg edema assessment and management. Med Surg Nursing, 23(1), 44-53. Retrieved from Utica College.