(CHEST 2001; 119:1586-1589) A 29-year-old white man was seen in a local pinch department with complaints of fatigue.

(CHEST 2001; 119:1586-1589)

A 29-year-old white man was seen in a local pinch department with complaints of fatigue, night sweats, cervical and inguinal lymphadenopathy, nausea, and right-upper-quadrant pain. His illness began when he evolveed a sore throat and weakness. He was treated with amoxicillin and had near improvement in symptoms over the nearest 2 days.

This patient had no significant medical or surgical history, was receiving no long-term medications, and had no known unsalable article allergies. He never smoked and had no history of illicit physic use.

Physical Examination

forward presentation to the emergency department, the patient appeared dyspneic and jaundiced. He had a legumes rate of 104 beats/min; BP 90/40 mm Hg; and temperature, 394 [degrees] C Oxygen saturation onward room air was 91%. He had marked cervical and inguinal adenopathy, an erythematous oropharynx, bronchial breath unbrokens bilaterally, and splenomegaly.

Laboratory Findings

WBC hold was 9,500 cells/L, with 31% polymorphonuclear small cavitys 57% lymphocytes with 21% atypical lymphocyte and 12% monocytes. Total bilirubin horizontal was 7.6 mg/dL; direct bilirubin, 61 mg/dL; aspartate aminotransferase, 280 IU/L; alanine aminotransferase, 566 IU/L; and alkaline phosphatase, 463 IU/L. Coagulation studies, electrolyte measurements, and renal function proceeds were normal. A chest radiograph showed bilateral hilar adenopathy and bilateral alveolar and interstitial infiltrates (Fig 1)

[ILLUSTRATION OMITTED]

Clinical Course

He was started upon IV levofloxacin and admitted to a hospital upon hospital day (HD) 2, the patient's liver function proofs improved, but he developed worsening dyspnea and hypoxemia. Arterial kin gas analysis on 2 L/min of oxygen through nasal cannula showed a pH of 748; [PCOsub2] 31 mm Hg; and [POsub2] 60 mm Hg An abdominal ultrasound revealed no obvious pathologic condition. A CT scan of the chest (Fig 2) showed hilar adenopathy and bilateral parenchymal infiltrates. CT of the abdomen and pelvis showed diffuse adenopathy with splenomegaly. arises of a sputum Gram's stain were negative. Ampicillin/sulbactam and fluconazole treatment was started.

[ILLUSTRATION OMITTED]

An inguinal lymph node biopsy obtained onward HD 3 revealed a reactive lymph node with paracortical hyperplasia. The patient continued to be febrile. Imipenem was added to his antibiotic regimen. upon HD 4, the patient bring outed worsening dyspnea, was intubated, and was transferred to our institution.

Physical examination in our ICU was essentially unchanged, save that the patient was intubated and sedated, and had bring to maturityed a nonblanching macular rash onward his torso and eyelids. Arterial posterity gas analysis on 100% oxygen and 10-cm [Hsub2]O positive end-expiratory crushing was pH of 7.37; [PCOsub2] 42 mm Hg; and [POsub2] 106 mm Hg

What diagnostic example would you order?

What is the etiology of this man's hypoxic respiratory failure?

Answer: Heterophile antibody screen; Epstein-Barr virus pneumonia

Infectious mononucleosis (IM) is an acute febrile illness of children and young adults with an incidence of 38/100000 It is generally a benign, self-limited multisystem lymphoproliferative disease caused on the Epstein-Barr virus (EBV). The EBV is a ubiquitous DNA virus of the herpesvirus assemblage The respiratory tract is a major reservoir for EBV and the epidemiology of IM moves a respiratory mode of transmission. It has also been put in mind ofed that the disease is likely spread by means of intimate oral contact in young adults, and therefore is known as the "kissing disease."

Typically, patients not past nor future between the ages of 15 years and 25 years, with the classic triad of heat pharyngitis, and lymphadenopathy. Periorbital edema and splenomegaly are usually construct on physical examination. Older patients with IM may instant a diagnostic dilemma, as they frequently do not have typical features. Up to 80% of patients with IM evolve a rash when they are given ampicillin.

Laboratory studies usually reveal an increase in mononuclear lonely dwellings of [is greater than] 50% with at least 10% atypical lymphocyte and a positive heterophile antibody proof result. In addition, findings of liver function examples are commonly abnormal. The serologic basis for the diagnosis of IM is a positive heterophile proof result and tests specific for EBV antibodies. However, up to 22% of patients with IM may have a negative heterophile exhibition result. The EBV antibody example is highly sensitive for IM, and the lack of any EBV antibodies withholds the disease.

Life-threatening complications rarely flash on the mind with an estimated mortality rate between 03% and 1% The mostly common of these complications include upper-airway obstruction, splenic hostility autoimmune hemolytic anemia, thrombocytopenia, hepatitis, myocarditis, and meningoencephalitis.

A clinical syndrome of "atypical pneumonia" has been described in 3 to 5% of patients with IM and is characterized from mild respiratory complaints, such as a paroxysmal nonproductive cough which may or may not be associated with radiographic abnormalities. Pulmonary infiltrates with IM have an incidence ranging from 3 to 5% to as high as 10% Other chest radiographic findings with IM include splenomegaly (47%) hilar adenopathy (15 to 136%) and cardiac enlargement with pulmonary venous hypertension (2%) Other pulmonary manifestations of IM include superimposed bacterial pneumonia, atelectasis, pleuritic pain, and pleural effusions.

...