A 12-year-old black girl is hospitalized because of increasinglysevere dyspnea and sore throat. The sorethroat started about a week earlier and was accompaniedby fever and chills. The patient was evaluated at an urgentcare center when her symptoms worsened, where she wasgiven ampicillin for a presumptive “strep throat.” A generalizedmaculopapular erythematous rash developed within24 hours of the start of therapy, and the ampicillin waspromptly withdrawn. The rash cleared gradually thereafter.Now the patient’s sore throat has worsened to the pointthat she has difficulty with drinking and eating. She hasbecome increasingly dyspneic during the past 24 hours.
12-year-old black girl is hospitalized because of increasinglysevere dyspnea and sore throat. The sorethroat started about a week earlier and was accompaniedby fever and chills. The patient was evaluated at an urgentcare center when her symptoms worsened, where she wasgiven ampicillin for a presumptive "strep throat." A generalizedmaculopapular erythematous rash developed within24 hours of the start of therapy, and the ampicillin waspromptly withdrawn. The rash cleared gradually thereafter.Now the patient's sore throat has worsened to the pointthat she has difficulty with drinking and eating. She hasbecome increasingly dyspneic during the past 24 hours.The child has no history of recurrent infections,cough, chest pain, palpitations, or seizures. She has beennauseated but has had no vomiting, hematemesis, or melena.She reports a dull aching pain in the left upper quadrant.She denies headache, vision problems, weakness,and neck stiffness. Her urinary output is scanty and highcolored.She has no known allergies, and her immunizationsare up-to-date.The patient is a well-built, well-nourished young girlwho looks ill and who is in moderate respiratory distress.Her pulse rate is 100 beats per minute; temperature,38.1
F); respiratory rate, 30 breaths per minute;supine blood pressure, 90/60 mm Hg; standing bloodpressure, 78/48 mm Hg. Skin, mucous membranes, andtongue are dry. The tonsils are grossly erythematous, enlarged,and almost touching each other in midline. Thereis a grayish white exudate over the tonsils. An expiratorystridor is audible.Skin shows fading rash. Cervical, anterior and posteriorchain, submandibular, axillary, and inguinal glandsare enlarged, discrete, nonmatted, and nontender. Theankles are not swollen.The chest moves symmetrically and is resonant topercussion; bronchovesicular sounds are audible bilaterally.No wheeze or rales are heard. Jugular venous pressureis normal; the apex is within normal limits, and both heartsounds are audible without any murmur or gallop.The liver is 3 cm below the costal margin, and thespleen is 9 cm below the costal margin. Bowel sounds arenormal.The patient is neurologically intact.
The white blood cell (WBC) count is 21,000/μL, with21% polymorphonuclear leukocytes, 72% leukocytes, and16% atypical lymphocytes. Hemoglobin level is 12.6 g/dL;platelet count, 212,000/μL; erythrocyte sedimentationrate, 88 mm/h.
What abnormalities does the peripheral smear show,and to which of the following disorders does theclinical picture point?
Clinical features of infectious mononucleosis are listedin the
Associated sequelae are rare; most patientsrecover fully in 4 to 6 weeks. When complicationsdo occur, however, they can be dramatic and often lifethreatening.
In most infected patients, leukocytosis is observed;the WBC count ranges from 10,000/μL to 20,000/μL.Atypical lymphocytes may account for 10% to 80% of totallymphocytes. Mild thrombocytopenia is transient. In thegreat majority, there is mild to moderate elevation of liverenzyme levels--particularly transaminases--to about 2 to3 times normal.Detection of heterophil antibodies with the monospottest is the characteristic laboratory abnormality. Theseantibodies are detected in 90% of patients with infectiousmononucleosis, although the test takes up to 3 weeks tobecome positive. Therefore, repeated testing may be necessary--especially if the initial test is performed early.Several commercially available monospot tests are helpfulin making the diagnosis. The heterophil antibodies usuallydisappear by 3 months but may be present for up to ayear. False-positive monospot test results are rare but canoccur in patients with varicella, influenza, or lymphoma.EBV infection can also be detected by the presenceof other specific antibodies. Routine use of virus-specificantibody detection is not needed but may be helpful in patientswith atypical cases of EBV infection or in youngchildren who can be heterophil antibody-negative. Titersof IgM and IgG antibodies to EBV viral capsid antigen(VCA) are elevated in more than 90% of patients at theonset of the disease. Simultaneous detection of EBV earlyantigen also helps confirm the diagnosis.
Infectious mononucleosis is usually self-limited. Theduration of infection varies; the acute phase lasts about 2weeks. Generally, about 20% of patients can return to workor school within 1 week, and 50%, in 2 weeks. Fatigue maynot resolve fully for 2 to 4 weeks. Fewer than 1% of thoseinfected die--usually from splenic rupture, encephalitis,or severe airway obstruction.
Therapy is largely supportive. Patients need to restduring the acute phase. For those with splenomegaly,heavy lifting and contact sports should be avoided for 2months (to protect against splenic rupture). Acetaminophen or an NSAID can be used as an antipyretic insteadof aspirin (to prevent the remote possibility of Reyesyndrome).The role of corticosteroids in uncomplicated caseshas been extensively studied--and they are
advocated.Nevertheless, these agents have been very useful in patientswith impending airway obstruction, myocarditis,hemolytic anemia, or encephalitis.Antiviral therapy with acyclovir has been shown tolimit oropharyngeal viral shedding, but it has no impacton the clinical course.
OUTCOME OF THIS CASE
The patient in this case had a throat culture negativefor group A streptococci; blood cultures were also negative.Results of urinalysis were normal, and urine culturewas negative. Serum sodium level was 130 mEq/L;potassium, 3.1 mEq/L; chloride, 92 mEq/L; bicarbonate,21 mEq/L; glucose, 98 mg/dL; urea nitrogen, 26 mg/dL;creatinine, 1.1 mg/dL; serum bilirubin, 2.6 mg/dL;bilirubin, direct, 1.9 mg/dL; protein, 6.9 g/dL; albumin,4.3 g/dL; aspartate aminotransferase, 126 IU; alanineaminotransferase, 102 IU; alkaline phosphatase, 222 IU.Findings on chest films and an ECG were normal. Themonospot test was positive. Epstein-Barr panel revealedearly antigen, 1:150, VCA 1:280. Epstein-Barr nucleolarantigen was absent.The patient was given intravenous fluids, and treatmentwith parenteral hydrocortisone, 100 mg every 8hours, was started. Within 24 hours she became afebrile,was breathing with less difficulty, and was able to takesips of water. Three days after the start of therapy, hertonsils were smaller and she was able to tolerate a softdiet. She was discharged on the fourth day on a regimenof oral prednisolone in tapering doses.
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