An 18-month-old female presents with fever, erythema, swelling around umbilicus

Issue: February 2012

An 18-month-old female presents to the office with a low-grade fever and an area of erythema and swelling about the umbilicus. The history of the chief complaint began the day before when the mother suspected that the child had injured her abdomen while playing with a toy car, over which she fell. She did not think much of it at first, but then the patient was noted to have fever to 101.5·F that evening.

James H. Brien, DO

The next day, her primary noted the area of concern (Figure 1) and ordered a plain abdominal radiograph (Figure 2), which the radiologist noted had a “non-specific opacification about the umbilical area” and recommended a CT scan.

The patient’s past medical history is that of a previously healthy child, with no history of any significant medical or surgical problems. Her prenatal and birth history was normal, and her immunizations are up-to-date. As noted, there was a thought by the mother of possible abdominal trauma, but nothing witnessed. She lives with both parents and two siblings. There is no history of recent travel, animal exposure or sick contacts.

Figure 1: A primary noted the area of concern.

Figure 2: The doctor ordered a plain abdominal radiograph.

Examination revealed only the noted findings; specifically, a normal female with some painful induration and erythema about the umbilicus with an otherwise normal abdomen. The rest of her examination was normal. Basic lab tests include a white blood cell count of 29,600 cells/mcL with 71% neutrophils and 16% band forms, anion gap of 16 mmol/L and a C-reactive protein of 7.7 mg/L. The abdominal/pelvic CT scan is represented in Figures 3, 4 and 5.

Figure 3: The abdominal/pelvic CT scan is represented in Figures 3, 4 and 5.

Figure 4

Figure 5

What’s Your Diagnosis?

A. Abdominal wall cellulitis

B. Omphalitis

C. Infected urachal cyst

D. Funisitis

The answer turned out to be an infected urachal cyst (C). The urachus is a structure that represents the remnants of the embryonic cloaca and the allantois. It normally becomes a fibrous band from the bladder to the umbilicus. However, it may retain its tubular anatomy, thus providing a potential space as a nidus for infection. This can be seen on the images of the CT scan, revealing the fluid-filled lesion extending from the umbilicus inferiorly toward the bladder (Figure 6). Because of the apparent infection and metabolic acidosis, the hospital team started the patient on a combination of vancomycin plus piperacillin-tazobactam (Zosyn, Wyeth Pharmaceuticals), pending surgical drainage, which was done promptly and revealed copious, thick yellow exudate (Figure 7). The Gram stain revealed Gram-positive cocci and the culture grew methicillin-sensitive Staphylococcus aureus. S. aureus is the cause in most cases; however, other Gram-positive cocci and Gram-negative rods can be there as well.

Figure 6: The images of the CT scan reveals the fluid-filled lesion extending from the umbilicus inferiorly toward the bladder.

Figure 7: The hospital team started the patient on a combination of vancomycin plus piperacillin-tazobactam, pending surgical drainage, which was done promptly and revealed copious, thick yellow exudate.

Her blood culture was negative, and her treatment was changed to nafcillin for the remainder of time in the hospital. She was sent home on oral cephalexin to complete a 2-week course of therapy with complete resolution of the infection. She returned 1 month later for elective urachal cystectomy. This two-stage surgical approach is preferred over a single-stage drainage and excision because it is usually associated with fewer complications and a shorter time in the hospital.

Abdominal wall cellulitis may involve the umbilical area, but the difference is usually not subtle and is associated with an obvious break in the skin as shown in Figures 8 and 9, a case of methicillin-resistant S. aureus cellulitis. These can be very scary infections, especially if associated with varicella, which is more likely to lead to necrotizing fasciitis, as shown in Figure 10, a fatal case from Michael Cater, MD. Fortunately, this is much less common now that varicella has been vaccinated down to an occasional curiosity.

Figure 8: Abdominal wall cellulitis may involve the umbilical area, but the difference is usually not subtle and is associated with an obvious break in the skin as shown in Figures 8 and 9, a case of methicillin-resistant S. aureus cellulitis.

Figure 9

Figure 10: These can be very scary infections, especially if associated with varicella, which is more likely to lead to necrotizing fasciitis.

Omphalitis and funisitis only occur in neonates. Omphalos is the Greek word describing the stone in the temple of Apollo and thought to represent the center of the universe. Funis or funiculus is derived from the Latin word for rope or cord. Umbilicus is derived from the Latin word for center. Therefore, the funiculus umbilicus is the center cord. Because of the confusion associated with these terms, in the mid-1980s, Alice Cushing, MD, proposed changing the terminology of this troublesome infection to be “true omphalitis” and “uncertain omphalitis” (as opposed to funisitis). However, this never caught on, and we are back to the old terminology.

“True” omphalitis (Figure 11) is a potentially lethal infection if in the abdominal wall about the umbilical cord, with potential for deep tissue extension, and is usually caused by S. aureus, group A strep (Streptococcus pyogenes) and occasionally gram-negative bacilli. The pre-eminent anaerobic infection expert, Itzhak Brook, MD, has also shown the significant role of anaerobes in this infectious disease. Therefore, empiric antimicrobial treatment, pending appropriate culture and sensitivity results, should include choices that will cover for these organisms. One might select an anti-pseudomonas cephalosporin or penicillin plus an anti-staph agent (clindamycin or vancomycin if septic-appearing) and possibly metronidazole if clindamycin is not being used. Other choices may be equally effective.

Figure 11: “True” omphalitis is a potentially lethal infection if in the abdominal wall about the umbilical cord, with potential for deep tissue extension.
Image: Weir Mike

Figure 12: The patient may still present with a malodorous umbilicus with a superficial infection of the skin around the area.

Funisitis literally means inflammation of the cord. This usually results in a wet, foul-smelling umbilical stump and is usually caused by inflammation driven by group A strep. Even after the stump falls off, the patient may still present with a malodorous umbilicus with a superficial infection of the skin around the area (Figure 12), somewhat like impetigo. This is usually a result of poor cord care (hygiene) and can usually be treated with good cleaning and possibly a topical antimicrobial ointment. Some experts recommend a single dose of penicillin G with topical treatment and close follow-up. If “uncertain,” get advice from your friendly infectious disease consultant (we need the work). I would like to thank the department of Pediatric surgery at The Children’s Hospital at Scott and White for their help with this case.

Columnist Comments

I have received many comments about the passing of Heinz Eichenwald, as mentioned in the December issue. Most had no idea that he had died, and I’m sure many younger readers had no idea who he was.

Gen. Douglas MacArthur famously said in his retirement address to Congress in 1951, “Old soldiers never die; they just fade away.” I believe this is the case with many great people who happen to retire and live out a normal lifespan. If you are sort of average and want to be remembered, arrange an untimely, preferably tragic death, and your accomplishments will be magnified many times over, and you’re more likely to be remembered by a generation who never knew you.

Of course, I’m being a bit facetious. I think most of us would much rather live anonymously for a long time and be forgotten in the end. In that column, John Nelson, MD, pointed out to me that the legend under the picture of Heinz showing his wife, Linda, and my wife, Ellen, had our wives misidentified; causing me to have to explain to Ellen how such a mistake could be made before I became history myself. Knowing Heinz, he would have seen the humor in this as well.

James H. Brien, DO, is a member of the Infectious Diseases in Children Editorial Board as well as Vice Chair for Education at The Children’s Hospital at Scott and White and is the Associate Professor of Pediatrics at Texas A&M University, College of Medicine, Temple, Texas. email: jhbrien@aol.com. Disclosure: Dr. Brien reports no relevant financial disclosures.