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.
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.
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.
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.
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.
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.
Lastly, I typically do not promote meetings in this column; one of the
exceptions being the Uniformed Services Pediatric Seminar (USPS). An excellent
general pediatric meeting, sponsored by the Uniformed Services Section of the
AAP, will be held next month (March 10-13) at the Renaissance Seattle Hotel in
Seattle. If interested, everything you need to know can be found on this
website:
www.pedialink.org/cmefinder/brochures/2012USPSBrochure.pdf.
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.