Phenytoin-induced thrombocytopenia treated with intravenous immune globulin.

PURPOSE: To describe the use of intravenous immune globulin (IVIG) in an 8-year-old girl with phenytoin-induced thrombocytopenia and leukopenia. PATIENTS AND METHODS: An 8-year-old girl had fever, rash, thrombocytopenia, and leukopenia 18 days after initiation of phenytoin therapy. The phenytoin level was elevated. She was treated with 1 g/kg of IVIG. RESULTS: The thrombocytopenia improved dramatically after IVIG therapy. There was a slower response to the leukopenia. CONCLUSIONS: Phenytoin hypersensitivity can present with thrombocytopenia and leukopenia. Treatment with IVIG was associated with a rapid rise in the platelet count in the patient in this report. IVIG should be considered for patients with phenytoin-induced thrombocytopenia.

Transmission of varicella-vaccine virus from a healthy 12-month-old child to his pregnant mother.

A 12-month-old healthy boy had approximately 30 vesicular skin lesions 24 days after receiving varicella vaccine. Sixteen days later his pregnant mother had 100 lesions. Varicella-vaccine virus was identified by polymerase chain reaction in the vesicular lesions of the mother. After an elective abortion, no virus was detected in the fetal tissue. This case documents transmission of varicella-vaccine virus from a healthy 12-month-old infant to his pregnant mother.

Relevance of the catheter hub as a portal for microorganisms causing catheter-related bloodstream infections.

Microorganisms causing vascular catheter-related sepsis gain access to the bloodstream through either the skin at the catheter insertion site or through the catheter hub. The catheter insertion site is probably the predominant portal for microorganisms in catheters in place for a short time, but the catheter hub may play an increasingly important role in infection in association with long-term catheters, particularly those that are subcutaneously tunneled. Although transient contamination of the catheter hub does not cause infection, certain microorganisms may migrate endoluminally and enter the bloodstream, causing bacteremia or fungemia.

Duration of tick attachment as a predictor of the risk of Lyme disease in an area in which Lyme disease is endemic.

Animal studies have shown an exponential increase in the risk of Borrelia burgdorferi infection after 48-72 h of deer tick attachment. Persons with tick bites were prospectively studied to determine if those with prolonged tick attachment constitute a high-risk group for infection. Ticks were identified, measured for engorgement, and assayed by polymerase chain reaction (PCR) for B. burgdorferi DNA. Duration of attachment was determined from the scutal index of engorgement. Of 316 submissions, 229 were deer ticks; 14% were positive by PCR. Paired sera and an intact tick for determination of duration of attachment were available for 105 subjects (109 bites). There were 4 human cases (3.7% of bites) of B. burgdorferi infection. The incidence was significantly higher for duration of attachment > or =72 h than for <72 h: 3 (20%) of 15 vs. 1 (1.1%) of 94 (P = .008; odds ratio, 23.3; 95% confidence interval, 2.2-242). PCR was an unreliable predictor of infection. Tick identification and measurement of engorgement can be used to identify a small, high-risk subset of persons who may benefit from antibiotic prophylaxis.

Meningococcemia.

Meningococcal infection is a contagious disease that is spread via the respiratory route through pharyngeal secretions. Clinical manifestations range from occult bacteremia to overwhelming septicemia or meningitis. Skin manifestations often develop and may be the first sign that leads to clinical suspicion of meningococcemia. Treatment consists of antibiotic therapy and supportive care, which may include aggressive fluid resuscitation, oxygen, ventilatory support, and inotropic support. The use of chemoprophylaxis and in certain circumstances vaccination are important in preventing secondary cases of meningococcal disease.

Intravenous catheter-related infections.

Vascular catheter-related infection is an important cause of mortality and morbidity in hospitalized patients. The mean incidence of catheter-related bloodstream infection in hospitalized pediatric patients is 2.4 episodes per 1,000 days. Totally implantable central venous catheters may be associated with a lower risk of infection. Coagulase-negative staphylococci are the predominant cause and account for about one third of episodes of catheter-related bloodstream infection. The diagnosis of catheter-related bloodstream infection is often difficult because there are frequently no signs of inflammation around the catheter. Diagnosis depends on either a positive quantitative catheter culture yielding the same microorganism recovered from the bloodstream or differential quantitative blood cultures with significantly greater colony counts from blood drawn through the catheter than from blood drawn through a peripheral vein. Alternatively, probably catheter-related sepsis can be diagnosed when clinical sepsis is refractory to antimicrobial therapy but responds to catheter removal. Often these criteria are not met but catheter-related bloodstream infection is presumed because a common skin microorganism is isolated from the blood when clinical manifestations of bloodstream infection are present and there is no other apparent source of infection. Microorganisms causing catheter-related bloodstream infection gain access to the bloodstream predominantly from either the catheter insertion site or the catheter hub. Most catheter-related infections occurring shortly after catheter insertion probably gain access to the bloodstream by extraluminal migration along the catheter from the skin at the catheter insertion site. When catheters are in place for extended periods, especially greater than 30 days, the catheter hub probably plays a major role in microorganisms gaining access and then migrating endoluminally until reaching the bloodstream. Recently employed strategies for the prevention of catheter-related infections include topical antibiotics or antiseptics at the catheter insertion site, flush solutions containing vancomycin, and bonding antimicrobial agents to the catheter. Infection of peripheral and central venous catheters generally resolves after catheter removal. For tunneled silicone catheters, most episodes of catheter-related infection can be initially managed with antimicrobial therapy infused through the catheter without catheter removal. Staphylococcus aureus is generally more aggressive and associated with more complications than coagulase-negative staphylococci. Microorganisms that usually require catheter removal include Candida and Bacillus species. Adjunctive treatments of catheter infections include the use of urokinase. Catheter-related infection remains an important complication of vascular access. Novel prevention and treatment strategies are currently being investigated. In the near future bonding of antibiotics or other agents to catheters may become routine.(ABSTRACT TRUNCATED AT 400 WORDS)

Use of disinfectants to reduce microbial contamination of hubs of vascular catheters.

The vascular catheter hub is a potential portal of entry for microorganisms that cause catheter-related sepsis. Thus, a reduction in catheter hub contamination might reduce the incidence of catheter-related sepsis. To develop a regimen suitable for reducing microbial contamination of the catheter hub, we experimentally contaminated catheter hubs and assessed the efficacies of disinfectant solutions. Catheter hubs were incubated overnight with suspensions of Staphylococcus epidermidis, Pseudomonas aeruginosa, or Candida parapsilosis. After removal of unattached microorganisms, the catheter hubs were swabbed by rotating cotton swabs dipped in 1% chlorhexidine, 1% chlorhexidine in 70% ethanol, 70% ethanol, 97% ethanol, or normal saline. Posttreatment swabs of the catheter hub were obtained and cultured quantitatively. The cleaning regimens containing ethanol were the most effective. Seventy percent ethanol was more effective than chlorhexidine and is likely to be the safest treatment. We conclude that cleaning of the catheter hub with disinfectant can dramatically reduce microbial contamination.

A prospective study of the catheter hub as the portal of entry for microorganisms causing catheter-related sepsis in neonates.

The hypothesis that catheter-related sepsis (CRS) may be preceded by contamination of the catheter hub was tested in neonates with central venous catheters. Cultures of the catheter hub were obtained three times per week. One hundred thirteen catheters were placed in 88 patients. Of 35 episodes of sepsis, 28 were catheter-related, for a catheter sepsis rate of 1.03/100 catheter-days. CRS occurred in 26 (23%) of 113 catheters. In 10 of 28 episodes, the infecting microorganism was cultured from the hub before its culture from blood obtained at the time of clinical sepsis. In an additional 5 cases, a culture of the catheter hub at the time of clinical sepsis yielded the same isolate as the blood culture. Thus, 54% of episodes of CRS were preceded by or coincided with contamination of the hub. The catheter hub may be a major portal of entry for microorganisms causing sepsis in a neonatal intensive care unit.

Ocular manifestations of Mycoplasma pneumoniae infection.

Ocular manifestations of Mycoplasma pneumoniae infection, other than conjunctivitis, are uncommon. Optic disk swelling, optic nerve atrophy, retinal exudates and hemorrhages, and cranial nerve palsies have been infrequently reported. We describe a 15-year-old patient who developed bilateral optic disk edema and iritis during an acute infection with M. pneumoniae and review the world literature on findings associated with ocular manifestations of infection with this pathogen. Although our patient experienced complete resolution of iritis and optic disk edema after 6 weeks, several patients described in the literature have experienced permanent sequelae as a result of optic neuropathy.

Passive smoking and croup.

The relationship between croup and the presence of household cigarette consumption was assessed in a matched-pair case control study. Fifty subjects with a primary hospital discharge diagnosis of croup were paired with children with a primary hospital discharge diagnosis of abdominal hernia. The results yielded an estimated relative risk of 0.82. The power of this study to detect a relative risk of 2.0 was 38%. This study fails to show a relationship between passive smoking and croup in early childhood.