A febrile toddler presents with acute leg pain, swelling

Issue: September 2013

ByJames H. Brien, DO

A previously healthy 3-year-old female was admitted to the hospital with fever and painful swelling of her right lower leg. The history of this problem began rather suddenly the day before, with some mild erythema in a band-like distribution and painless swelling in the same area, after walking in some tall grass during an outing at a family ranch. There was no recollection of any injury or insect bite. A few hours later, she awoke from her nap complaining of some pain and a limping gait, and was then noted to be febrile at 101.6°F. The erythema and swelling had worsened, so she was then taken to the local ED where she was treated with a dose of IV ceftriaxone and clindamycin and referred for admission.

James H. Brien

Her medical history was that of a healthy 3-year-old female whose immunizations were up to date. Her family history is also unremarkable with no sick contacts or anyone else with any skin problems.

On examination, she was alert, febrile (102°F) and mildly tachycardic, with normal blood pressure and respirations. Her capillary refill was brisk. Her right lower leg was found to have an irregular-shaped, well-demarcated, circumferential area of bright erythema with some swelling and blister formation in places (Figures 1 and 2). Additionally, there was some erythematous streaking along the medial aspect of her right knee and thigh (Figure 3). Her white blood cell count was 22,700. The blister was sterilely aspirated for Gram stain and culture. The Gram stain was negative and the culture is pending. Plain X-rays of the leg are normal.

Her right lower leg was found to have an irregular-shaped, well-demarcated, circumferential area of bright erythema with some swelling and blister formation in places (Figures 1 and 2).

Images: Brien JH

Additionally, there was some erythematous streaking along the medial aspect of her right knee and thigh (Figure 3).

What’s Your Diagnosis?

A. Group A streptococcus

B. Staphylococcus aureus

C. Necrotizing fasciitis

D. Snake bite

The wound culture grew group A strep (GAS; Streptococcus pyogenes). Treatment with ceftriaxone and clindamycin were used initially, then penicillin G when results were known. Some of the characteristic features of GAS infections include:

Rapid onset and progression;
Associated with sepsis/lymphangitis/erysipelas;
Not responsive to sulfa drugs (Septra);
May provoke necrotizing fasciitis, especially with varicella; and
May elude the effects of penicillin: Eagle (Inoculum) Effect — main rationale for using a beta-lactam plus clindamycin.

Features of Staphylococcus aureus soft tissue infections may overlap with the above, but tend to be more contained with abscess formation and a bit slower progression. Both can result in toxic shock syndrome and can cause necrotizing fasciitis (Figure 4), which is more common with GAS, and often associated with concurrent varicella.

Envenomation from a snake bite usually results in immediate pain, swelling and, sometimes, coagulopathy, especially with rattlesnake bites (Figure 5). A young child with an unwitnessed bite might pose a diagnostic challenge unless bite marks are found. The sudden onset and rapid swelling usually makes it easy to rule out a primary infection. However, secondary infections with unusual organisms may accompany snake bites due to the heavy colonization of their mouth with a variety of gram-negative enterics and common gram-positive cocci. S. aureus still leads the list.

GAS and S. aureus can result in toxic shock syndrome and can cause necrotizing fasciitis (Figure 4). Envenomation from a snake bite usually results in immediate pain, swelling and, sometimes, coagulopathy, especially with rattlesnake bites (Figure 5).

Columnist Comments

As we are still in the warmer months (at least in Texas, where, as of this writing, the temperatures are still in the upper 90s), skin and soft tissue infections are still occurring at a fairly high rate. This usually mirrors outdoor activities, with its associated minor injuries and bites that open the port-of-entry through which bacteria can invade. But soon, as we move on into the fall and early winter, the balance shifts from skin and soft tissue infections to respiratory infections; from minor rhinovirus upper respiratory tract infections to respiratory syncytial virus, influenza and lower respiratory tract infections. So, remember to call in those at high-risk patients for RSV prophylaxis, and all children aged 6 months and older for influenza vaccine.

This would seem to be a good time to remember our beloved colleague, Caroline (Caren) Breese Hall, MD, who died last December. She was not only a friend to everyone she met, she contributed most of what we know about RSV; creating much knowledge about respiratory tract infections. I count myself very fortunate to have known her. While she was small in size, she was a giant in our field; and like many of the giants of pediatrics and infectious diseases, I first learned of Caroline from Jim Bass during my fellowship (1982-1984). He would discuss Caroline’s work at length, ultimately drawing comparisons with her father, Burtis Breese, who Jim also greatly admired, particularly for his landmark work with group A streptococcus, the subject of this column.

What a great legacy; and while these outstanding physician scientists can never be replaced, I have great confidence that our specialty and subspecialties are rich with talented young physician leaders and investigators; all beginning to build on their own legacies.

Refrences:

Eagle H. J Exp Med. 1948;88:99-131.

For more information:

James H. Brien, DO, is vice chair for education in the department of pediatrics at McLane Children’s Hospital at Scott & White/Texas A & M College of Medicine in Temple, Texas. He is also a member of the Infectious Diseases in Children Editorial Board.

Disclosure: Brien reports no relevant financial disclosures.