A twenty-year-old male soldier was admitted to the Department of Internal
Medicine with suprapubic pain, fever, and an erythematous rash on his chest,
which had developed five days prior to admission. During the month before the
onset of the disease, he had been engaged in strenuous physical activity
associated with his military service and in additional exercise that included
playing basketball and taking a two-mile daily run. The medical history was
notable for chronic Leishmania skin lesions, which had appeared during his
service in the desert. These lesions, caused by Leishmania tropica,
which is endemic in the Middle East, developed gradually and manifested a
characteristic dry, crusted, ulcerative
appearance10. The
cutaneous lesions had persisted for three months before his admission. There
was no history of drug abuse.
The patient had a temperature of 38.5°C, a blood pressure of 100/60
mmHg, and a regular pulse of 90 bpm. He had an erythematous rash on his face
and neck and minimal neck lymphadenopathy. Three erythematous concave, raised,
and crusted lesions of 0.5 cm in diameter, typical of cutaneous
Leishmaniasis15,
were found on the right cheek and right hand. The lungs were clear, and the
heart sounds were normal. The abdomen was not tender, and the liver and spleen
were not enlarged. There was extreme suprapubic tenderness extending to the
left groin without local edema, heat, or discoloration. Small, non-tender
bilateral inguinal lymph nodes were palpated. There were no signs of
thrombophlebitis of the lower extremities.
The peripheral white blood-cell count was 6300/mm3 with 65%
granulocytes, the sedimentation rate was 66 mm, and the findings on urinalysis
were normal. A skin biopsy specimen from one of the lesions confirmed the
diagnosis of cutaneous Leishmaniasis. A pelvic radiograph demonstrated
osteolytic lesions of the pubic ramus bilaterally
(Fig. 1). A technetium-99m bone
scan revealed a focus of enhanced uptake in the symphysis pubis and the left
superior pubic ramus and a smaller focus in the right pubic bone
(Fig. 2). Enhancement was seen
on all three phases of the scan. A computed tomography scan of the pelvis
(Fig. 3) revealed an osteolytic
area on the anterior aspect of the left pubic ramus and mild swelling of the
soft tissues. Needle aspiration from the left pubic ramus performed prior to
antibiotic treatment yielded purulent fluid. A gram stain revealed numerous
gram-positive cocci and polymorphonuclear cells. Bacterial culture yielded a
pure heavy growth of methicillin-sensitive Staphylococcus
epidermidis. Repeated blood cultures were negative. The patient was
treated with intravenous cloxacillin for six weeks, with resolution of the
pain and fever and resumption of physical activity. The patient was free of
symptoms at the one-year follow-up examination.
We found eighteen reported cases of pubic osteomyelitis in athletes,
including our patient, in a review of the
literature5-14.
A summary of the clinical data is provided in the Appendix. Seventeen cases
occurred in men. The average age (and standard deviation) was 25 ± 10
years (range, twelve to forty-eight years). All patients were active athletes
who participated in strenuous physical activity. However, a specific traumatic
event was noted for only two of the eighteen patients. In addition, only three
patients had specific skin lesions that may have been a port for
bacteremia.
The major clinical symptom is pain in the groin or adjacent areas that
radiates to the thigh. Limitation of motion is common, and local tenderness
and swelling may occur. A high temperature is usually noted. An elevated
erythrocyte sedimentation rate and leukocytosis, although common, are not
always evident.
In most of the eighteen patients, the diagnosis was delayed. The average
time from the start of symptoms to diagnosis was thirteen days (range, one to
thirty days). Changes in plain radiographs of the pubic bone usually appear
only several weeks after the clinical presentation of osteomyelitis and
therefore are not reliable in making the diagnosis. Typical changes include
pubic rarefaction and osteolysis. Sclerosis may appear later. A technetium
bone scan shows increased uptake and may facilitate an earlier diagnosis. In
three patients, the diagnosis was made only after aspiration and culture.
Blood cultures may be positive; however, in patients with a highly
suspicious case, early bone aspiration or biopsy will facilitate the
diagnosis. In most of the cases reviewed, the infectious agent was identified
(see Appendix). The most common pathogen was Staphylococcus aureus,
which was identified in cultures of blood or local aspiration.
The main differential diagnosis of pubic osteomyelitis is osteitis pubis.
Osteitis pubis is a painful, noninfectious, self-limited inflammatory
condition of the pubic bone associated mainly with genitourinary surgery, but
it also occurs following minor trauma or as a manifestation of overuse in
athletes14. Whereas
the initial clinical symptoms of the two entities may be similar, the presence
of fever and progressive clinical deterioration favors an infectious process
and emphasizes the need for repeated cultures.
The cornerstone of treatment is antibiotic therapy. In the cases reviewed,
the duration of treatment varied from four weeks to six months. Six weeks of
antibiotic treatment typically resulted in a good clinical response without
complications. Surgical treatment should be considered in patients with a
complicated course that does not respond to antibiotic
treatment3,16.
Two other groups at risk for the development of pubic osteomyelitis are
intravenous drug abusers and patients undergoing genitourinary
surgery3,4.
A comparison of the clinical features in the three risk groups is presented in
Table I. The clinical
presentation, contributing factors for the development of osteomyelitis, the
pathogens, and the treatment seem to be distinct for the three groups. The
clinical symptoms and signs, in particular a high fever, are almost always
present in athletes, but they are frequently absent in patients who have
development of pubic osteomyelitis after genitourinary
surgery4. In
athletes, minor skin abrasion allowing bacteremia with seeding to the pubic
bone is the putative reason that Staphylococcus aureus is the
predominant pathogen. In intravenous drug abusers, the most common pathogen is
Pseudomonas aeruginosa, associated with hematogenous seeding. In
patients after genitourinary surgery, the infection usually follows some
technical complication of the procedure and the pathogens, gram-negative
bacteria, stem from contamination of the surgical
wound4. The
therapeutic approach is also different among the groups. In athletes and drug
abusers, antibiotics are usually sufficient, whereas patients who have had
surgery frequently require some form of surgical intervention in order to
minimize
complications4.
It is still unclear why athletes are at risk for the development of this
rare condition. This entity commonly occurs in specific athletic endeavors,
such as football or running, that involve strenuous physical exercise and may
produce excessive stress to the pelvis. In addition, it has been suggested
that the immune system in athletes may be compromised during strenuous
exercise, which perhaps increases their susceptibility to transient bacteremia
caused by minor skin
trauma17; however,
this issue is debatable. Finally, a preexisting subclinical osteitis pubis may
make the athletes locally susceptible to osteomyelitis. In our patient,
Staphylococcus epidermidis grew on a culture of fluid from the bone
aspiration. To our knowledge, Staphylococcus epidermidis has not been
previously reported as a cause of pubic osteomyelitis. Repeated local
irritation of the chronic Leishmania skin lesions in our patient could have
served as a port of entry and predisposed the patient to transient
bacteremia.
In conclusion, pubic osteomyelitis should be suspected in athletic
individuals with sudden groin pain and fever. The pathogenesis is obscure and
is possibly due to local trauma of the pubic bone caused by stress combined
with minor skin trauma causing seeding of the bacteria. The clinical diagnosis
depends on a high index of suspicion. Radiographic changes are delayed; early
findings may be seen in bone scans. The diagnosis should be established by
blood culture or needle aspiration of the pubic bone. Treatment with
intravenous antibiotics should be started early and continued for six weeks,
with a high expectation that the infection will resolve.
A table presenting a summary of a literature review of the cases of pubic
osteomyelitis in athletes is available with the electronic versions of this
article, on our web site at
(go to the article citation and click on "Supplementary Material")
and on our quarterly CD-ROM (call our subscription department, at
781-449-9780, to order the CD-ROM).