DR. LAYTON is a pediatric hospitalist at Peninsula Regional Primary Care, Peninsula Regional Medical Center, Salisbury, Md.
DR. SIBERRY is an assistant professor of pediatrics in the divisions of general pediatric and adolescent medicine and pediatric
infectious diseases at Johns Hopkins Hospital, Baltimore.
The authors and section editor have nothing to disclose in regard to affiliations with, or financial interests in, any organization
that may have an interest in any part of this article.
You are the pediatric hospitalist at a community hospital, and the particular chart in your hands this morning belongs to
a 6-year-old African-American boy admitted to your service the evening before by the pediatrician on call. The saga of this
patient, who has no previous medical history, began four days earlier when he was brought to the emergency department by his
family, complaining of fever and chest pain.
In triage that day, the boy's temperature was 38.6C; heart rate, 114/min; and respirations, 18/min. Oxygen saturation was
99% on room air. He rated the chest pain as "10" on a scale of 1 to 10--10 being the worst possible pain. He was given acetaminophen
according to triage protocol. The fever and chest pain both eased, and the family left the ED before a physician could see
the boy.
Next day, fever and chest pain returned and he was brought back to the ED. Temperature was now 39.7C; heart rate, 108/min;
and respirations, 22/min. Oxygen saturation had fallen to 96% on room air, and he now rated his pain as "7." The chart indicates
an unremarkable physical exam and a normal chest radiograph. No other studies were performed. A diagnosis of pleurisy was
made in the ED and the patient was discharged with instructions for ibuprofen.
The pattern repeated itself the following day: The boy's temperature rose to 40.1C and the chest pain returned and persisted.
This time, however, his mother brought him to the ED of a tertiary care hospital. There, another chest radiograph was taken
and a diagnosis of "air under the diaphragm"--you presume that means colonic air--was made. He was again discharged, and his
mother was instructed to give him Fleet enemas and continue the ibuprofen. Neither blood tests nor an electrocardiogram were
obtained at the tertiary care hospital, according to the mother.
He must be enduring dj vu, too
Yesterday, the boy was brought back to the ED at your hospital because of persistent fever and chest pain. The chart notes
that the chest pain was localized on the left side; he described it as "the worst pain ever"--sharp, stabbing, lasting 40
to 60 minutes, and returning approximately every three hours. Pain radiated to the back, became worse on deep inspiration,
and was relieved somewhat with ibuprofen. There was no associated shortness of breath or diaphoresis.
And so it goes in the chart. The history is negative for trauma or GI symptoms. The boy denies cough, symptoms of a respiratory
tract infection, genitourinary symptoms, vomiting, diarrhea, joint pain, and rash. A complete review of systems is negative.
The medical history is insignificant. The boy does not take medication. Immunizations are up to date. He lives with his mother,
father, and two siblings. He is in the first grade. The mother has a history of hypothyroidism, hypertension, and gallstones;
the father carries the sickle cell trait. There is a family history of kidney stones and unspecified heart disease.
In the ED yesterday, the boy's vital signs were as follows: temperature, 37.8C; heart rate, 120/min; respirations, 24/min;
and blood pressure 100/84 mm Hg. Oxygen saturation was 99% on room air. He rated the pain "10" again.
The physical exam was unremarkable. He was described as moaning in the triage room but not doubled over, and was able to answer
questions appropriately. Pulmonary, cardiac, and abdominal examinations were normal. The chest wall was not tender to palpation.
He was given morphine for pain.
A complete blood count was unremarkable: white blood cell count, 8.0 X 103/μL, with a normal differential count; hemoglobin,
12.9 g/dL; and platelet count, 296 X 103/μL. Urinalysis was unremarkable. Because of the colicky nature of the pain, abdominal
and pelvic spiral computed tomography was performed; the scan was negative for kidney stones. An ECG was normal for age.
Specimens were obtained for blood and urine cultures and the boy was admitted and started on intravenous ceftriaxone.
Since admission at 7 p.m. last night, he has had a low-grade fever and intermittent severe chest pain that has been treated
with acetaminophen, with some relief.
Differential, interrupted
Before you go to see this boy, you consider causes of chest pain with fever in children (see the table):
- Can this be a case of pneumonia or pneumothorax? That's unlikely-three chest radiographs were reported normal-but you make a mental note to review the films yourself.
- Trauma or costochondritis? Typically, these conditions aren't associated with fever.
- Myocarditis or pericarditis? Here are the most worrisome possibilities, but you would expect cardiac findings, such as an abnormal ECG and cardiomegaly
on the chest radiographs. You plan to pay careful attention to the cardiac exam.
- What about pulmonary embolism? That would be an uncommon cause of chest pain in a child his age without associated risk factors.
- And pleurisy? Whether caused by coxsackie B virus infection, endocarditis, systemic lupus erythematosus, or familial Mediterranean fever,
this remains high on the differential.
Chest pain, normal chest radiograph: The differential diagnosis
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As you finish considering the differential, your patient cries out in pain. You hurry to his room and find him writhing in
bed. A quick (but difficult) exam shows that the temperature is 37.7C; respirations, 22/min; and heart rate, 106/min. The
BP is 110/58 mm Hg. Oxygen saturation is still 99% on room air. Head, neck, eyes, ears, nose, mouth-all are unremarkable on
exam except for multiple dental caries. He points to his left lower chest and the epigastric region of his stomach when you
ask where the pain is worst. He also tells you that his entire abdomen hurts. You continue your inspection.
The lungs are clear without wheezing, rales, or rhonchi. The heart rate and rhythm are regular and without murmur, rub, or
gallop. Palpation does not exacerbate the chest pain. You see no evidence of trauma to the chest wall. The abdomen is soft
and nondistended, without hepatosplenomegaly.
The patient complains of diffuse abdominal tenderness on palpation, worse in the epigastric region. There is no guarding or
rebound. The genitourinary exam is unremarkable. You see no rash or evidence of active synovitis in the joints; no Osler nodes,
no Janeway lesions, no splinter hemorrhages. Clearly, he is in a great deal of pain, so you prescribe a stat dose of morphine
and begin rethinking the differential.
Reproducible pain now scores a "2"
With the associated abdominal pain, you add cholecystitis, pancreatitis, and reflux esophagitis to the differential diagnosis.
You decide to order more laboratory tests. Amylase and lipase levels are normal. Liver function tests are within normal limits.
The troponin level is <0.04 ng/mL. The erythrocyte sedimentation rate is 32 mm/h (upper limit of normal, 10 mm/h) and the
C-reactive protein (CRP) level is 41 mg/L (upper limit of normal, 3.3 mg/L).
You reexamine the patient after he has been given morphine. He sits comfortably in bed. On questioning, he reports that his
pain is now "2," and complains solely of left lower-chest pain and very mild epigastric pain. When you examine him, you determine
that the chest pain is clearly reproducible when you palpate the left lower ribs, especially at the left costochondral junction.
Why, you wonder, was the pain not present on palpation earlier? You attribute that to the severity of his pain when you first
examined him. He also has very mild epigastric pain on palpation.
Reproducible rib pain is typical of costochondritis--but how do fever and an elevated CRP level fit in? Why is the pain unilateral?
Fever, focal bone pain, and elevated CRP lead you to consider osteomyelitis, but you've never heard of rib involvement.
Blood culture and bone scan add up
About the time you're contemplating that possibility, a call comes from the microbiology lab: Blood culture is growing gram-positive,
coagulase-positive cocci in clusters. You add vancomycin to cover methicillin-resistant Staphylococcus aureus and order a bone scan.
The scan is positive for abnormal increased uptake of radioactive tracer in the anterior aspect of the left fifth rib. Although
the radiologist advises that these findings could indicate infection or neoplasia, the positive blood culture leads you to
conclude that the patient's illness must be osteomyelitis of the rib!
Conclusive results of the blood culture reveal methicillin-sensitive S aureus. You switch the antibiotics to oxacillin, and a PICC line is placed.
Rare, in the rib
After four days, your patient is afebrile with minimal pain, a repeat blood culture is negative, and the CRP level has fallen
to 1.9 mg/L. The boy is discharged on IV antibiotics, and you plan for follow up with the pediatric infectious disease consultant
to determine the appropriate duration of the IV antibiotic therapy.
The patient follows up at the pediatric infectious disease clinic of the tertiary care hospital. After two weeks of IV antibiotics,
the CRP level has normalized and his pain has resolved. He is switched to oral cephalexin (Keflex) to complete a six-week
course.
Rib osteomyelitis accounts for fewer than 1% of cases of osteomyelitis in children1--which alone can make it difficult to diagnose. In a review of 106 cases of bacterial rib osteomyelitis, average time to
diagnosis was, remarkably, 16 weeks.2
The disease can be diagnosed with a bone scan, as it was in this case; diagnosis is also possible with ultrasonography, a
plain film, or CT when a high index of suspicion exists. With any of these imaging modalities, the findings that suggest osteomyelitis
may also indicate neoplasia, and biopsy of the lesion may be required for definitive diagnosis.3 S aureus is the causative agent in most reported cases of rib osteomyelitis, although mycobacterial and fungal infections have also
been implicated.1-3
REFERENCES
1. Donovan RM, Shah KJ: Unusual sites of acute osteomyelitis in childhood. Clin Radiol 1982;33:220
2. Bishara J, Gartman-Israel D, Weinberger M, et al: Osteomyelitis of the ribs in the antibiotic era. Scand J Infect Dis 2000;32:223
3. Basa NR, Ming S, Fombe N: Staphylococcal rib osteomyelitis in a pediatric patient. J Pediatr Surg 2004;39:1576
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