Seroepidemiological study of infectious mononucleosis in older patients

Clinical features and costs of care for hospitalized adults with primary Epstein-Barr virus infection

PURPOSE

To study the clinical and laboratory features of primary infection with the Epstein-Barr virus in adults who required hospitalization and to assess the difficulty in its diagnosis, the use of diagnostic procedures, and the associated costs of care.

PATIENTS AND METHODS

We retrospectively identified all adult patients who were diagnosed with primary Epstein-Barr virus infection in our region between 1988 and 1997 using strict serologic criteria. The added costs of unnecessary diagnostic tests and treatment were estimated.

RESULTS

The analysis included 47 patients (60% men) with a mean (+/-SD) age of 30 +/- 14 years. The prime cause of admission was fever (83%). Compared with patients 35 years of age and older, those younger than 35 years were more likely to have pharyngitis (45% vs 10%) and lymphadenopathy (66% vs 17%). Younger patients also had a greater mean atypical lymphocyte count (17% +/- 14% vs 8% +/- 6%) and more abnormal hepatic enzyme levels. Inpatient work-ups resulted in 309 days of hospitalization, many diagnostic tests, and unnecessary empiric treatments (total 203 days of antibiotic therapy). Overall, unnecessary diagnostic procedures and medical treatments contributed an average of approximately $12,000 in health-care costs per patient.

CONCLUSIONS

Testing for primary Epstein-Barr virus infection should be a routine step in the investigation of fever in adults of all ages. A higher index of suspicion might prevent unnecessary, sometimes hazardous inpatient work-ups from being performed, thereby reducing health-care expenses.

Fever of unknown origin in elderly patients

OBJECTIVE

To describe the spectrum of diseases that may give rise to fever of unknown origin in elderly patients and to delineate the diagnostic approach in these patients.

DESIGN

Subgroup analysis of a prospectively collected case series followed more than 2 years.

SETTING

General Internal Medicine Service based at University hospital, Leuven, Belgium.

PATIENTS

Forty-seven consecutive patients, older than 65 years, meeting the classic criteria of fever of unknown origin.

MEASUREMENTS

The final diagnosis established and the clinical value of diagnostic procedures.

RESULTS

Infections, tumors and multisystem diseases (encompassing rheumatic diseases, connective tissue disorders, vasculitis including temporal arteritis, polymyalgia rheumatica, and sarcoidosis) were found in 12 (25%), six (12%) and 15 patients (31%), respectively. Drug-related fever was the cause in three patients (6%), miscellaneous conditions were found in five patients (10%), and six patients (12%) remained undiagnosed. Microbiologic investigations were diagnostic in eight cases (16%), serologic tests yielded one diagnosis, immunologic investigations had a diagnostic value in four cases, standard X-rays yielded a diagnostic contribution in 10 cases, ultrasonography and computed tomography were diagnostic in 11 cases, Gallium scintigraphy had a diagnostic contribution in 17 cases, and biopsies yielded the final diagnosis in 18 cases.

CONCLUSIONS

Multisystem diseases emerged as the most frequent cause of fever of unknown origin in the elderly, and temporal arteritis was the most frequent specific diagnosis. Infections, particularly tuberculosis, remain an important group. The percentage of tumors was higher in our elderly patients than in the younger ones but still clearly lower than in other recent series of FUO in adults. The number of undiagnosed cases was significantly lower in elderly patients than in younger individuals (P < or = 0.01). The investigation of elderly patients with FUO should encompass routine temporal artery biopsy and extensive search for tuberculosis if the classic tests such as blood count, chemistry, urinalysis, cultures, chest X-rays, and abdominal ultrasonography do not yield any clue. Gallium scintigraphy should be considered as the next step and not as a last-resort procedure.

Viruses and the blood

Haematological syndromes attributed to viruses demonstrate geographical variations in incidence and great dependence on host factors. Severe haematological disease is the exception rather than the rule in dengue virus infection, and probably depends at least in part on the host immune response to the virus. The increased incidence of hepatitis-associated aplasia in east Asia may reflect distribution of an infectious agent, an environmental toxin, or genetic predisposition, but probably represents some combination of these factors. Agents with apparently universal distribution, such as parvovirus B19 and Epstein-Barr virus, are associated with bone marrow failure only in a very narrow range of hosts. These examples teach us that viral causes cannot automatically be excluded from the differential diagnosis of syndromes whose occurrence is rare or apparently sporadic. Further investigation of these syndromes should include more detailed characterization of host factors, particularly immunological characteristics, and possible infectious and toxic cofactors which are associated with morbidity.