The uncommon but lethal infection known as necrotizing fasciitis continues to be in the news. This is a devastating disease that can be difficult to diagnose in the early stages. The first presentation is often nothing more than arm or leg pain that looks very much like garden-variety musculoskeletal discomfort. By the time the diagnosis is made, the disease process is often too far along to reverse it, resulting in severe disability or death. However, there are usually a few clinical clues that a more dangerous process is under way.

Consider the following case of necrotizing fasciitis to identify the clues that can assist you in the early diagnosis of this life- and limb-threatening infection.

Day 1: Emergency Department Visit #1

A 38-year-old man presented to the emergency department with a complaint of left foot pain. His vital signs in triage were: BP 124/76, Temp 100.4˚F (38˚C), Pulse 116, Resp 20.

• History: 36-year-old male with pain along the sole of his foot starting last night, worse today. Walking is exquisitely painful. Patient thought this might be a circulatory problem, but recalls he was not injured. He did not twist or hurt his foot. He is on his feet a great deal during work.
• Relevant Physical Exam: “The foot is exquisitely tender along the plantar fascia starting at the heel, ending at the head of the metatarsals. X-ray negative for fracture.”
• ED Course: The emergency physician diagnosed “Plantar Fasciitis.” He ordered taping of the foot, crutches, ice, elevation, and anti-inflammatory medication. He discharged the patient with instructions to follow up with his primary care physician in 2 days. His abnormal vital signs were not repeated.

Day 3: Office Follow-Up Visit

During the office visit two days later, BP was 114/80, Pulse 136. He had severe swelling of his foot and ankle, with pain up to the knee. He was unable to bear weight due to pain. His physician noted: “No warmth or redness observed. Foot pulse is good. Repeat X-ray shows no fracture.”

The physician diagnosed “ankle sprain,” prescribed acetaminophen with codeine, applied an air cast, and instructed the patient to elevate the ankle and return for re-check in 1 week.

Day 4: Emergency Department Visit #2

The patient returned to the same ED complaining of redness and swelling to the left foot and ankle. Vital signs were: BP 110/64, Temp 98.1˚F (36.7˚C), Pulse 144, Resp 28.

• History: “Left foot to knee pain and swelling for 5 days. Saw PMD, diagnosed ankle sprain. Called PMD yesterday and was started on an antibiotic.”
• Emergency Physician Evaluation: The patient was markedly diaphoretic. There was marked edema, erythema, and increased warmth to touch from the toes to the knee. There were large confluent vesicles over the dorsal and lateral aspects of his left foot and hemorrhagic vesicles on the lateral aspect of the foot. WBC was 42,000. The patient was admitted with a diagnosis of necrotizing fasciitis. The emergency physician started ceftriaxone in the ED, 2 grams IVPB, and consulted surgery and infectious disease.
• Hospital Admission Summary: Surgery and infectious disease agreed that the patient had necrotizing fasciitis and compartment syndrome. He underwent debridement and irrigation of the left leg and foot, decompression, and fasciotomy. The wounds improved. Cultures showed Group A Streptococcus. Blood cultures were negative. The patient had a second operation for definitive debridement.

What should have happened during the first ED visit on Day 1?

Standard of care aside, this emergency physician should have recognized the key features of fever, tachycardia, and severe pain without injury. The presentation was not well explained by the diagnosis of plantar fasciitis. The physician should have considered infection in the differential diagnosis and ordered diagnostic studies. Early surgical consultation would have been appropriate. The nurses should have repeated vital signs according to department protocol and should have alerted the emergency physician that he was discharging a patient with abnormal vital signs.

What should have happened during the office visit?

The primary care physician should have recognized that the pulse rate of almost 140 beats/min was dramatically abnormal. He also should have realized that plantar fasciitis does not somehow morph into a sprained ankle. When considered together, those two facts must indicate that something more serious was occurring.

Look at the common threads found in this and other cases of delayed or missed diagnosis of necrotizing fasciitis:

1. There is often no visually apparent site of infection.
2. There is usually an abnormal vital sign reflecting a significant physiologic abnormality.
3. There is often pain out of proportion to mechanism of injury.
4. Onset is often minutes to hours.
5. There is often minor trauma to the area.
6. The physician’s medical reasoning does not connect the dots with a diagnosis that explains the presentation.

It is absolutely key to make this diagnosis early, as any delay in diagnosis results in increased morbidity and mortality. In two decades of case review, we have yet to find an alleged failure to diagnose necrotizing fasciitis that did not demonstrate early abnormal vital signs or pain significantly out of proportion to the mechanism of injury.

References

• Hakkarainen T, et al. Necrotizing soft tissue infections: Review and current concepts in treatment, systems of care, and outcomes. Curr Probl Surg. 2014; 51(8):344-362.
• Stevens D, et al. Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections: 2014 Update by the Infectious Disease Society of America. Clinical Infectious Diseases. 2014; 59(2):147-59.