Erysipelas

                                  Dr. KS Dhillon

Introduction

Erysipelas is a skin infection that involves the dermis layer of the skin. It can also extend to the superficial cutaneous lymphatics. Erysipelas is characterized by an area of erythema which is well-demarcated and raised. It usually affects the lower extremities, with the face being the second most commonly affected site. It is also referred to as “St. Anthony’s Fire” due to the intense fiery rash. Its diagnosis can overlap with cellulitis. Often a definite diagnosis cannot be made. As compared to cellulitis which has ill-defined borders and is slower to develop, erysipelas has better-defined borders and develops faster. Although erysipelas can be serious it is rarely fatal. It responds rapidly and favorably to antibiotics. Usually, local complications are more common than systemic complications. Group A streptococci is the most common cause.

Etiology

In this infection, streptococci are involved. Facial infections are usually due to Group A streptococcus. Lower extremity infections are usually caused by non-group A streptococcus. A prospective study in Norway by Rath et al (1) showed that beta-hemolytic streptococci were the leading cause of facial cellulitis (1). The leading cause of postpartum erysipelas in neonates is Group B streptococcus. Erysipelas starts with a break in the skin which leads to inoculation of the bacteria. Insect bites, surgical incisions, stasis ulcerations, and venous stasis are among the several entry portals. Facial erysipelas can also be caused by nasopharynx infection.

In the literature, there is little evidence to show that staphylococcus plays a role in erysipelas (2).

The risk factors for erysipelas include:

• Excision of the saphenous vein for bypass

• Post-surgery (e.g. mastectomy)

• Nephrotic syndrome

• Lymphatic edema (major risk factor)

• Lymphatic obstruction

• Arteriovenous fistula

• Immunocompromised state

Epidemiology

Many of the epidemiological studies on erysipelas have been done in different settings in different countries. Erysipelas can affect people of all races, age groups, and sex. There are some studies that show that erysipelas is more common in females. With the development of antibiotics and improved sanitation, the incidence of erysipelas has decreased. Erysipelas is most common in the extremes of age but it can affect individuals of all age groups (3).

Pathophysiology

A break in the skin leads to skin infection. It directly invades the lymphatic system and causes erysipelas. Surgical incisions, stasis ulceration, insect bites, and venous insufficiency are possible portals of entry into the skin. Some risk factors for the development of erysipelas are eczema, obesity,  lymphedema, leg ulcers, athlete’s foot, intravenous drug abuse, liver disease, and poorly controlled diabetes. Recurrent erysipelas have also been reported. The infection typically reoccurs at the same site (4).

Histopathology

Histopathology will show dermal edema, significant vascular dilatation, and invasion of bacteria into the connective tissue and lymphatics. Invasion of blood vessels is rare.

History and Physical

The diagnosis of erysipelas is clinical. Obtaining a history of any recent skin trauma or pharyngitis is important. Patients with erysipelas usually have systemic symptoms, such as fever, malaise, and chills 48 hours before developing the skin lesion. Erysipelas presents as an area of skin erythema with raised edges. Patients usually complain of itchiness, burning, and tenderness at the site. In patients with more severe disease, there can be bullae, vesicles, and even frank necrosis.

It is important to know the location of inflammation. In patients with lower limb erysipelas, examining the interdigital toe spaces for scaling, fissures, or maceration is important. The presence of redness and swelling involving a joint should raise suspicion of other more serious disease processes like septic arthritis.

Evaluation

For the diagnosis of erysipelas, no laboratory tests are needed. Elevated ESR, leukocytosis, and elevated C-reactive protein are common. The outcome of these investigations will not change the management or the treatment plan for otherwise healthy individuals. Blood cultures are not routinely obtained since they have a low yield. However, blood tests and cultures are useful in the immunocompromised, and ill-appearing patients. 

Extensive workup should be carried out in patients with prosthetic heart valves, in patients who may be intravenous drug abusers and in those with other intravascular devices. Patients with sepsis will require a full workup and resuscitation.

Management

When erysipelas is suspected antibiotics against streptococci should be started. Penicillin remains the first-line antibiotic for the treatment of erysipelas. Antibiotic coverage against MRSA remains controversial. The  Infectious Diseases Society of America (IDSA) 2014 guidelines for the diagnosis and treatment of skin and soft tissue infections (5) recommend coverage against MRSA in patients “whose cellulitis is associated with penetrating trauma, evidence of MRSA infection elsewhere, nasal colonization with MRSA, injection drug use, or SIRS”.  Most patients with erysipelas can be discharged from the hospital with oral antibiotics. The antibiotics are usually given for 5 days, the period however can be extended to 10 days if the infection is not controlled. Hospitalization is recommended if there is necrotizing infection, the patient is immunocompromised, the patient has poor adherence to medications and follow-up, and for patients whose outpatient treatment is not working.

Prophylactic antibiotics have been used in patients with recurrent cellulitis for over 40 years (6).

In a Cochrane analysis of five trials involving the use of prophylactic antibiotics, particularly penicillin showed that prophylactic antibiotics reduced the recurrence by 69% (7). 

A retrospective study by Rob and Hercogová showed that Benzathine penicillin G once every 3 weeks was effective prophylaxis for recurrent erysipelas. They however could not conclude how long the prophylaxis treatment was required (8). 

In patients who have 3 to 4 episodes of cellulitis per year, despite attempts to treat or control predisposing factors, the 2014 practice guidelines for the diagnosis and management of skin and soft tissue infections recommend oral penicillin or erythromycin twice a day for 4 to 52 weeks, or intramuscular benzathine penicillin every 2 to 4 weeks. Patients with fever are provided with hydration, cold compresses, and acetaminophen. Surgical debridement is necessary for patients with abscesses or gangrene. Infants, elderly, and immunocompromised individuals are usually admitted to the ward.

Differential Diagnosis

Some diseases can mimic erysipelas (9). These diseases all present with edema, erythema, pain, and warmth. Some of the more serious conditions include necrotizing fasciitis, orbital cellulitis, septic bursitis, DVT, septic arthritis, phlegmasia cerulea dolens, flexor tenosynovitis, and toxic shock syndrome.  The less serious conditions include gout, felon, cellulitis, abscess, and paronychia.

Prognosis

The prognosis of erysipelas is usually good. The patient can be treated in the outpatient setting. Response to oral antibiotics is usually good. Extra caution has to be taken in immunocompromised patients and in those with poor adherence to medication. In severe cases affecting those who are infants, immunocompromised, and the elderly, hospitalization for intravenous antibiotics is recommended. Close monitoring and observation is required in patients who are most likely not going to comply with instructions or complete their antibiotic course due to psychological or social reasons.

Complications

Complications arising from erysipelas can be serious. They, however, are rarely fatal. Some local complications arising from erysipelas include: Abscess formation

• Scarlet fever

• Meningitis

• Skin necrosis

• Hemorrhagic purpura

• Pneumonia

• Thrombophlebitis

• Bullous formation. 

Yang et al (10) reported a case of erysipelas leading to bilateral lower limb and abdominal elephantiasis. Titou et al (11) carried out a retrospective study of 152 cases of erysipelas to evaluate the risk factors associated with local complications. They reported that prior antibiotics use and raised  ESR at the time of admission were independent risk factors for local complications of erysipelas. Local recurrence can occur in 5-20% of the patients. Local recurrence can lead to scarring.

Conclusion

Erysipelas is often seen in clinical practice. The diagnosis in most cases is clinical. The infection usually responds to antibiotics. The patients are usually treated in the outpatient department. Hospitalization is usually required if necrotizing infection is suspected, the patient is immunocompromised, the patient has poor adherence to medications and follow-up, and for those whose outpatient treatment has failed. Patients who undergo surgery for gangrene or an abscess may require long-term care. Medication compliance should be encouraged. The outcome for patients with erysipelas is good as long as they remain compliant with treatment.

References

1. Rath E, Skrede S, Mylvaganam H, Bruun T. Aetiology and clinical features of facial cellulitis: a prospective study. Infect Dis (Lond). 2018 Jan;50(1):27-34.

2. Karakonstantis S. Is coverage of S. aureus necessary in cellulitis/erysipelas? A literature review. Infection. 2020 Apr;48(2):183-191.

3. Klotz C, Courjon J, Michelangeli C, Demonchy E, Ruimy R, Roger PM. Adherence to antibiotic guidelines for erysipelas or cellulitis is associated with a favorable outcome. Eur J Clin Microbiol Infect Dis. 2019 Apr;38(4):703-709.

4. Galli L, Venturini E, Bassi A, Gattinara GC, Chiappini E, Defilippi C, Diociaiuti A, Esposito S, Garazzino S, Giannattasio A, Krzysztofiak A, Latorre S, Lo Vecchio A, Marchisio P, Montagnani C, Nicolini G, Novelli A, Rossolini GM, Tersigni C, Villani A, El Hachem M, Neri I., Italian Pediatric Infectious Diseases Society. Italian Pediatric Dermatology Society. Common Community-acquired Bacterial Skin and Soft-tissue Infections in Children: an Intersociety Consensus on Impetigo, Abscess, and Cellulitis Treatment. Clin Ther. 2019 Mar;41(3):532-551.e17.

5. Stevens DL, Bisno AL, Chambers HF, Dellinger EP, Goldstein EJ, Gorbach SL, Hirschmann JV, Kaplan SL, Montoya JG, Wade JC., Infectious Diseases Society of America. Practice guidelines for the diagnosis and management of skin and soft tissue infections: 2014 update by the Infectious Diseases Society of America. Clin Infect Dis. 2014Duvanel T, Mérot Y, Harms M, Saurat JH. Prophylactic antibiotics in erysipelas. Lancet. 1985;1(8442):1401. doi: 10.1016/s0140-6736(85 Jul 15;59(2):e10-52.

6. Duvanel T, Mérot Y, Harms M, Saurat JH. Prophylactic antibiotics in erysipelas. Lancet. 1985;1(8442):1401. doi: 10.1016/s0140-6736(85

7. Dalal A, Eskin-Schwartz M, Mimouni D, et al. Interventions for the prevention of recurrent erysipelas and cellulitis. Cochrane Database Syst Rev. 2017;2017(6). doi: 10.1002/14651858.CD009758.PUB2.

8. Rob F, Hercogová J. Benzathine penicillin G once-every-3-week prophylaxis for recurrent erysipelas a retrospective study of 132 patients. J Dermatolog Treat. 2018 Feb;29(1):39-43.

9. Blumberg G, Long B, Koyfman A. Clinical Mimics: An Emergency Medicine-Focused Review of Cellulitis Mimics. J Emerg Med. 2017 Oct;53(4):475-484.

10. Yang YP, Huang WX, Zhong WX, Fu YM, He PA, Zhao G, Feng QM. Bilateral Lower Limb and Abdominal Elephantiasis Due to Erysipelas. Chin Med J (Engl). 2018 Apr 05;131(7):873-874.

11. Titou H, Ebongo C, Bouati E, Boui M. Risk factors associated with local complications of erysipelas: a retrospective study of 152 cases. Pan Afr Med J. 2017;26:66.