Anne S. Yeager

Prevention of transfusion-acquired cytomegalovirus infections in newborn infants

Transfusion-acquired cytomegalovirus occurred in 13.5% of 74 infants of seronegative mothers who were exposed to one or more blood donors who had a CMV indirect hemagglutination titer of 1:8 or higher. None of 90 infants of seronegative mothers exposed only to donors with CMV IHA titers of less than 1:8 became infected. Ten of 41 (24%) infants of seronegative mothers who received more than 50 ml of packed red blood cells and who were exposed to at least one seropositive donor became infected. None of 23 infants of seronegative mothers who received this amount of blood but who were exposed only to seronegative donors became infected. Fatal or serious symptoms developed in 50% of the infected infants of seronegative mothers and in none of the 32 infected infants of seropositive mothers. Acquired CMV infections occurred in 15% of infants of, seropositive mothers who were exposed to the red blood cells of seropositive donors and in 17.6% of infants of seropositve mothers exposed only to seronegative donors. Use of seronegative donors reduced the prevalence of excretion of CMV among hospitalized infants who were 4 weeks of age or older from 12.5 to 1.8% and eliminated acquired CMV infections in infants of seronegative mothers.

Low Risk of Herpes Simplex Virus Infections in Neonates Exposed to the Virus at the Time of Vaginal Delivery to Mothers with Recurrent Genital Herpes Simplex Virus Infections

We studied the risk of herpes simplex virus (HSV) infections in neonates exposed to HSV at the time of vaginal delivery to mothers with a history of recurrent genital HSV infections. None of 34 infants exposed to HSV type 2 acquired an HSV infection. On the basis of this sample, the 95 percent confidence limit for the theoretical maximum infection rate is 8 percent. Cord blood or blood obtained during the first two weeks of life was available from 33 of the 34 exposed, uninfected neonates. All 33 of the samples possessed demonstrable neutralizing antibody to HSV type 2, and 79 percent had titers above 1:20. These results were compared with those in a previously studied group of neonates with HSV infections; the latter infants were significantly less likely at the onset of symptoms to have demonstrable neutralizing antibody to HSV type 2 (P = 0.000148) or to have titers above 1:20 (P less than 0.00001). We conclude that given the low attack rate, empirical antiviral therapy is not warranted in all infants of mothers with recurrent genital HSV infection who are exposed to the virus in the birth canal. Our findings suggest that the presence and titer of neutralizing antibody to HSV contribute to the low attack rate.

Failure of Antepartum Maternal Cultures to Predict the Infant's Risk of Exposure to Herpes Simplex Virus at Delivery

Abstract In 414 pregnant women with a history of recurrent genital herpes simplex infection, we studied the correlation between asymptomatic viral shedding in late pregnancy and at the time of delivery. Antepartum cultures for asymptomatic reactivation of herpes simplex virus were positive in 17 of the 414 women (4.1 percent). None of these women had positive cultures at the time of delivery. Cultures of specimens obtained at delivery from 5 of 354 asymptomatic mother–infant pairs (1.4 percent) were positive for asymptomatic excretion of herpes simplex virus. None of these women had had antepartum cultures that documented asymptomatic excretion of herpes simplex virus, despite the fact that culturing was repeatedly performed during the four weeks before delivery. Asymptomatic shedding of herpes simplex virus occurred with the same frequency at delivery, whether or not any episodes of symptomatic recurrence were noted during the pregnancy (1.4 vs. 1.3 percent). We conclude that antepartum maternal cultures...

Sequelae of maternally derived cytomegalovirus infections in premature infants

Eighteen of 106 (17%) infants of seropositive mothers, with birth weights less than 1500 gm, acquired cytomegalovirus from a maternal source. Neutropenia, lymphocytosis, thrombocytopenia, and hepatosplenomegaly developed in some infants concomitant with the onset of CMV excretion. Infected infants who excreted CMV at less than 7 weeks of age had longer oxygen requirements than infants who did not excrete CMV until they were older. Passively derived maternal antibody to CMV fell more rapidly over the first few months of life in sick premature infants than would be expected in term infants. Among six infected premature infants, five had undetectable antibody titers when CMV excretion began. Loss of passively acquired antibody and early excretion of virus appear to be associated with symptomatic CMV infections in premature infants of seropositive mothers.

Experimental Brain Abscess Evolution: Computed Tomographic and Neuropathologic Correlation

Brain abscess evolution was studied in dogs by correlating the CT appearance with the neuropathologic findings. The abscess, produced by direct inoculation, progressed from an area of cerebritis to a well encapsulated abscess over 14 days. Ring enhancement was seen in the cerebritis stage prior to capsule formation. The ring reached its maximum size at this stage and correlated best with the area of cerebritis surrounding the developing necrotic center; the rim of this ring increased in thickness, resulting in progressive diminution of the central lucent area on scans delayed up to 60 min. The diameter of the ring decreased as cerebritis receded. Once the capsule had formed, the central lucent area was similar and no longer filled in on delayed scans.

Neonatal herpes simplex infection in the absence of mucocutaneous lesions.

Six infants with disseminated HSV had no mucocutaneous lesions at any time during the course of the illness. These infants presented with lethargy, poor feeding, apnea, acidosis, and hepatomegaly. The diagnosis of HSV was made by culturing the infants oropharynx and blood, and the maternal cervix. Eight infants with HSV encephalitis had no skin, eye, or mucous membrane lesions. These infants presented with lethargy and low-grade fever, followed within 24 hours by the onset of focal partial motor seizures. The seizures were refractory to anticonvulsant therapy. The mean CSF white cell count was 131 cells/mm3;the glucose and protein concentrations were in the normal range. Brain biopsy was required for the early diagnosis of HSV encephalitis. These 14 cases presented 70% (14/20) of all infants with neonatal HSV diagnosed during the study period. HSV infection should be considered in infants with no mucocutaneous lesions who have signs usually associated with bacterial sepsis or who develop focal seizures during the first three weeks of life.

Sequelae of acquired cytomegalovirus infection in premature and sick term infants

To assess the risk of long-term sequelae after acquired cytomegalovirus (CMV) infection in premature and sick term infants, 55 CMV infected patients were matched prospectively with 55 control patients and these matched pairs were evaluated at 3 years of age. Sensorineural hearing losses were present in four of 43 CMV infected patients (all mild-moderate) and in two of 43 controls (one severe). The incidence of neurologic sequelae was not increased in CMV infected patients with birth weight greater than 2000 gm. Among patients with birth weight less than 2001 gm, moderately abnormal EEGs were found in four (17%) of 23 CMV infected patients and in one (4%) of 23 controls, and severe handicaps occurred in four (14%) of 29 CMV infected patients and in two (7%) of 29 controls. Severe handicaps in premature infants were significantly (P less than 0.05) associated with early onset of CMV excretion (less than 8 weeks of age) and severe cardiopulmonary disease. Among the premature infants who were documented early excretors, three of 13 had severe neuromuscular impairment, four of 13 had severe handicaps (DQ less than 70, severe neuromuscular impairment, or profound loss of vision or hearing), and an additional four had DQs of 70 to 79. Among their matched control subjects, none of 13 had severe neuromuscular impairment, two of 13 had severe handicaps, and an additional two had DQs between 70 and 79. None of the premature infants who were documented late excretors (greater than or equal to 8 weeks of age) had any neurologic sequelae. The risk of neurologic sequelae and handicap may be increased in premature infants with onset of CMV excretion in the first 2 months of life.

Use of the serum bactericidal titer to assess theadequacy of oral antibiotic therapy in the treatment of acute hematogenous osteomyelitis

Serum bactericidal titers against Staphylococcus aureus were measured in 63 children who were receiving mafcillin or methicillin intravenously, or dicloxacillin, penicillin, or cephalexin orally. The SBTs obtained following unit does of 25 mg/kg of dicloxacillin, 35 mg/kg of penicillin, or 25 mg/kg of cephalexin with probenecid were comparable to those seen following intravenous doses of 40 mg/kg nafcillin or methicillin. Twenty-two children with acute hematogenous osteomyelitis proven or presumed to be due to S. aureus were treated intravenously until point tenderness and fever had resolved, and then with oral therapy. The mean duration of intravenous therapy was 14 days. Oral doses were adjusted so that a peak SBT of greater than or equal to 1:16 and a trough SBT of greater than or equal to 1:2 were obtained in most children. No recurrences occurred. The SBT proved to be a practical means of assessing the adequacy of oral therapy in children with infections due to S. aureus.

Transmission of cytomegalovirus to mothers by infected infants: another reason to prevent transfusion-acquired infections.

Forty-seven percent of mothers who were seronegative to cytomegalovirus at the time an infected infant entered their home seroconverted within 12 months of exposure. In contrast the seroconversion rate was 2.4% among mothers of uninfected infants discharged from the same nursery and ranges from 1.4 to 2.6% in studies reported by others. All infants shed virus throughout the follow-up period. It was not possible to determine whether length of exposure or the age of the child were important factors in determining risk of seroconversion; however, most seroconversions occurred after the child had been home for 4 months or longer. Two mothers became pregnant while still seronegative. Transfusion-acquired infections are one avoidable source of transmission from infant to mother. Seronegative mothers in continuing contact with excreting infants are at risk of acquiring a cytomegalovirus infection and of transmitting it to their fetus should they become pregnant.

Neonatal acyclovir pharmacokinetics in patients with herpes virus infections

A preliminary analysis is presented of the pharmacokinetics of acyclovir in neonatal patients with herpes simplex virus infections. Mean peak acyclovir levels (microM +/- SD) at 5, 10, and 15 mg/kg per dose were 30.0 +/- 9.9, 61.2 +/- 18.3, and 86.1 +/- 23.5, with corresponding mean trough levels (microM +/- SD) of 5.3 +/- 3.4, 10.1 +/- 8.4, and 13.8 +/- 11.1, respectively. The mean half-life (t 1/2 beta) of acyclovir was 3.78 +/- 1.21 hours. The mean percent urinary recovery of acyclovir (+/- SD) at each dosage level was similar, with an overall mean recovery of 65 percent. The mean acyclovir concentration in urine did not exceed the solubility of acyclovir in bladder urine (1,300 micrograms/ml). Generally, neonatal acyclovir pharmacokinetics was consistent with previous reports from studies of adults.