More summertime problems to treat

A 6-year-old boy sustained an injury to his left arm when a piece of coat hanger wire flew out from under a lawn mower, producing a through-and-through penetrating wound just proximal to the elbow. He was seen in the emergency room where radiographs were obtained as shown in figures 1 – 3, revealing no bone injury.

Further examination revealed no apparent neurological or vascular injury and the wire was removed (figure 4). In the ER he was given a dose of ceftriaxone and sent home on trimethoprim/sulfamethoxazole to take for 10 days.

Seven days after the injury, the patient woke up with the area of injury a bit swollen with some minimal increase in discomfort, and was taken to his primary provider for evaluation, who also felt it to be slightly swollen. He was therefore referred for admission and intravenous antibiotics for presumed cellulitis. There has been no history of fever. Further history revealed that he had been doing so well that he participated in a Little League baseball game the night before admission, during which he used his left arm quite a bit.

His past medical history is that of a normal 6-year-old boy, with no significant medical or surgical problems prior to this accident and his immunizations are documented up to date.

Examination upon arrival to the children’s ward revealed normal vital signs and a normal examination except for the left arm, which did appear slightly larger just proximal to the elbow than the right arm (figure 5).

There was also noted a small, linear, erythematous mark adjacent to the entry wound as shown in figure 6, that according to the father was not there the day before, but he could not be sure about the night before after the game. The entry and exit wounds were scabbed over without any drainage or significant erythema around them (figures 7 & 8). The pulses distal to the injury were normal as well as his capillary refill, and a Doppler ultrasound revealed normal blood flow with no venous thrombosis. He had no sensory or motor deficits in the injured arm, and the rest of his exam was normal. Lab tests included a CBC, erythrocyte sedimentation rate and C-reactive protein, which were all normal/ negative. A blood culture is pending.

How Would You Treat?

1. Vancomycin IV
2. Clindamycin IV
3. No Antibiotics
4. Zosyn + Clindamycin

Case Discussion

I would not recommend any antibiotics for this patient (C) in that I feel the mild swelling, and probably the linear mark as well, seen on the day of admission was a result of having played in a baseball game the night before. Additional supportive facts include the lack of significant erythema, pain, fever, drainage, or abnormal lab tests. He was sent home the next day to continue trimethoprim/sulfamethoxazole, as previously prescribed, although he probably did not need it either, and to follow up with his primary provider. Subsequent evaluations document complete healing of the injury.

We, as pediatricians, are not often called on to deal with penetrating injuries, as trauma surgeons and pediatric surgeons typically manage them.

We occasionally see children who step on nails and sustain a penetrating injury to their foot, and we all know how to handle that, with its risk of Pseudomonas aeruginosa osteochondritis. But an injury like this patient had is a bit out of the ordinary for us.

The infectious complications of a penetrating injury are fairly broad depending on the circumstances: the type of projectile, environmental conditions that the patient was in (clean vs. dirty), when and what type of care received. This is the setting where an unusual organism may play a significant role, one that is perhaps “selected out” by the prophylaxis being used. As my old friend, Itzhak Brook, MD, points out in his excellent textbook, Pediatric Anaerobic Infections, Diagnosis and Management (2002, Marcel Dekker Inc.), anaerobic bacteria may be in the mix, and the environment of a penetrating injury may be ideal for these organisms to grow, especially if there is any associated vascular injury. One must also be concerned for possible bone involvement in these injuries. Usually, no fever, a normal WBC count and normal inflammatory markers (ESR, C-RP) significantly reduces the likelihood of osteomyelitis, as in the patient presented.

In any event, if a penetrating injury does become infected, antimicrobial therapy should always be based on culture and sensitivity of the drainage from the wound.

I think reasonable empiric coverage pending availability of culture results might include a combination of clindamycin for staph, strep and some possible anaerobes plus a broader-spectrum antibiotic like a third-generation cephalosporin or an anti-pseudomonas penicillin, like piperacillin-tazobactam (Zosyn). Other combinations may be equally as effective.

Also, consider the possibility of a retained piece of whatever the penetrating object was. The famous last words are, “I know we got it all out.” That was the story about the child in figure 9 who got a splinter of wood in his foot that was “completely removed” a week earlier. However, the podiatrist found a large piece left in (figure 10).

Staphylococcus aureus still leads the list of organisms recovered from wound infections. Much of the knowledge regarding penetrating wound infections come from the military experience, where penetrating injuries are very common, as shown in figures 11 – 13 (bullet wound, shrapnel and blast injuries, respectively, in patients brought to our hospital during Operation Desert Storm). When seen early, thoroughly debrided and cleaned, they usually don’t get infected. However, if there is a significant delay in getting to medical care, the chance of infection becomes almost 100%, such as the 3-year-old Iraqi child who came to our Combat Support Hospital in 1991 after sustaining an artillery injury to her left elbow, but was unable to get to medical care for several days (figure 14). Examination revealed much swelling and purulent drainage (figure 15), and a plain radiograph revealed severe bone injury and retained shrapnel (figure 16). She had no history of receiving immunizations, so she received tetanus immune globulin and tetanus toxoid. She was also given nafcillin and ceftriaxone and shipped out to an evacuation hospital in Saudi Arabia for definitive care.

The decision to give prophylactic antibiotics or not may depend on several of the factors mentioned above, and if used, should probably cover Staph (including MRSA) and possibly coliforms. This usually means using a combination of a couple of antibiotics, such as Clindamycin plus a broad-spectrum penicillin, such as Augmentin or a cephalosporin, such as Cefdinir. However, one must remember the limitations of antimicrobial prophylaxis: (1) compliance, (2) absorption and (3) resistance of the organism, making close follow-up very important.

Columnist comments

When I was a young boy growing up in the Dallas/Fort Worth area, an elderly adult friend of my parents sustained an above-the-ankle amputation in an accident involving a large mower. Sometime later, I recall a child that I knew whose eye was severely injured by flying debris from under his Dad’s mower. Lastly, my lab partner in medical school lost his right index finger reaching to pull out a limb stuck under his mower. There’s no age limit to these things.

In recent months, I have read of one child killed when he fell in front of his father’s riding mower as it was turning and another who lost a leg the same way. At the end of last summer, we had a young child in the hospital for several weeks with a severe shearing injury to her leg by the same mechanism. These are life-altering and life-threatening events that are, unfortunately, not rare. It’s a little bit like another summertime problem we see every year — drowning and near drowning. So, please remind your parents to keep their kids away from mowers and unattended swimming pools.

Next month I will feature another summertime problem. In the meantime, stay in the shade, and think about sending a care package to a soldier. As hot as it is here, I can assure you it is way hotter there.