Fever and rash in children: important diagnostic considerations.

The association of fever with illness has been known for years. A febrile child may have rash, and physicians need to know when this symptom combination is a benign versus a pathologic clinical presentation. In other terms, potential etiologies are either infectious or non-infectious. With scrupulous, methodical history taking and careful, serial physical examination, the treating physician will find hints to assess and solidify an appropriate diagnosis, and chose an appropriate treatment.

Mycobacterium triplex infection in a liver transplant patient.

Mycobacterium triplex was first named in 1996 as an acid-fast bacillus with features that most resemble Mycobacterium simiae and Mycobacterium avium-intracellulare complex but which possesses a distinct mycolic acid pattern as well as a distinctive 16S rRNA hypervariable region. It has been isolated from lymph node, sputum, and cerebrospinal fluid specimens, but to date only rare clinical cases of this organism have been reported in the literature. The following is a case report of M. triplex that was isolated from the pericardial and peritoneal fluid of a 13-year-old female liver transplant patient.

Parvovirus B19 infections.

Infections caused by human parvovirus B19 can result in a wide spectrum of manifestations, which are usually influenced by the patient's immunologic and hematologic status. In the normal host, parvovirus infection can be asymptomatic or can result in erythema infectiosum or arthropathy. Patients with underlying hematologic and immunologic disorders who become infected with this virus are at risk for aplastic anemia. Hydrops fetalis and fetal death are complications of intrauterine parvovirus B19 infection.

Sternal wound and mediastinal infections in infants with congenital heart disease.

The objective was to describe the epidemiologic, clinical, bacteriologic and therapeutic features of seven infants who developed sternal wound and mediastinal infections following palliation and/or repair procedures for congenital heart disease. A retrospective chart review was used. All infants with sternal wound and mediastinal infections were < 30 days of age at the initial operative procedure. Six of the infants had hypoplastic left heart syndrome, and one had complete transposition. Two infants required delayed closure of their chest wound. Three infants had superficial sternal infections and presented at a mean of 12 days postoperatively. Four infants had infection of the deep mediastinal structures: they were all asymptomatic and had purulent collections in their mediastinum at their second palliative operation, which was performed at a mean of 120 days after the initial surgery. Staphylococcus aureus, or coagulase-negative Staphylococcus, was isolated from the wound and/or blood of six infants. All infants with mediastinal infections were managed with operative debridement. Infants with superficial infections underwent local debridement. All infants received long-term intravenous antibiotics. Mediastinal infections in infants undergoing palliative staged procedures for congenital heart lesions may be chronic and indolent, resulting in delayed repair of congenital heart lesions.

Randomized, single-blinded comparative study of the efficacy of amoxicillin (40 mg/kg/day) versus standard-dose penicillin V in the treatment of group A streptococcal pharyngitis in children.

A 10-day course of amoxicillin at a dosage of 40 mg per kilogram per day was compared with conventional (lower dosage) penicillin V therapy in the treatment of culture-proven Group A streptococcal pharyngitis in children 3 to 18 years of age in a prospective, randomized, and single-blinded study. Children had to have signs and symptoms compatible with the diagnosis of streptococcal pharyngitis and to have a throat swab positive for Group A streptococci. A second throat culture was obtained 10 to 14 days after the completion of therapy. Serotyping was performed to help differentiate carrier states from reinfections. Of 161 children enrolled, 113 were evaluable; 55 received penicillin and 58 received amoxicillin. At the completion of therapy 70.9% (39/55) of patients in the penicillin group vs 87.9% (51/58) of patients in the amoxicillin group were asymptomatic (clinical cure, P = 0.025). At the completion of therapy, 54.5% (30/55) of patients in the penicillin group vs 79.3% (46/58) of patients in the amoxicillin group had negative throat cultures (bacteriologic cure, P = 0.005). The carrier rate (children who were well but who were still carrying the same serotype of Group A streptococcus) also differed between the groups: 13 (23.6%) in the penicillin group compared with six (10.3%) in the amoxicillin group. Amoxicillin at 40 mg/kg/day was significantly more effective than lower dosages of penicillin V for clinical and bacteriologic cure in the treatment of Group A streptococcal pharyngitis in children. The current perception that penicillin is declining in effectiveness may be due to inadequate dosing.

Parvovirus: a review.

Infections caused by human parvovirus B19 result in a variety of clinical manifestations, the severity of which depends on the immune and hematologic status of the host. Arthropathy is known to occur in children and adults with acute parvovirus B19 infection. In adults, the arthropathy is common and is usually brief and self-limited, although a chronic arthropathy due to HPV B19 infections can occur rarely. It is important to differentiate between such chronic infection and RA, because of the similar clinical manifestations and different modes of treatment. An association between HPV B19 and other rheumatologic diseases such as vasculitis needs further research before confirmation is possible.

Infectious diseases presentations of Munchausen syndrome by proxy: case report and review of the literature.

Munchausen syndrome by proxy is a form of abuse, usually of a child by a parent, in which a factitious illness is reported or produced in the child, resulting in unnecessary medical evaluations and treatments. A dramatic case of a 17-month-old infant with recurrent polymicrobial bacteremia prompted a review of cases diagnosed by the Pediatric Infectious Diseases consultation service at our referral children's hospital and a review of the infectious diseases presentations in the medical literature. The infectious diseases presentations of the syndrome as well as criteria for the diagnosis are reviewed and discussed.

Risk factors for penicillin-resistant systemic pneumococcal infections in children.

The purpose of this study was to identify risk factors that may differentiate children who develop systemic infections with resistant strains of Streptococcus pneumoniae from those who develop penicillin-susceptible pneumococcal infections. A retrospective case-controlled study was performed of all patients with positive blood and/or cerebrospinal fluid isolates for S. pneumoniae over a 13 1/2-month period. Patients with penicillin-susceptible strains of S. pneumoniae were compared with those with penicillin-resistant infections in terms of age, race, gender, diagnosis, underlying conditions, antibiotic therapy within 1 month prior to systemic infection, treatment, and outcome. Sixty-nine patients with systemic pneumococcal infections were identified over the study period. Nine (13%) of these patients had infection with a penicillin-resistant isolate. Six of these patients were infected with a relatively resistant strain (MIC 0.1-1.0 microgram/mL) while three were infected with a fully resistant strain (MIC > or = 2.0 micrograms/mL). There was no difference between the two groups in terms of age, race, gender, underlying diagnosis, treatment, or outcome. Sixty-seven percent of the patients who developed a penicillin-resistant pneumococcal infection had received antibiotics in the month prior to systemic illness versus 4% of those infected with a penicillin-susceptible strain (P < 0.0000097). In conclusion, when compared with children who develop systemic infection with a penicillin-susceptible strain of S. pneumoniae, children who develop infection with a penicillin-resistant strain are significantly more likely to have received antibiotics within 1 month prior to their illness.

Immunization with the immediate-early tegument protein (open reading frame 62) of varicella-zoster virus protects guinea pigs against virus challenge.

The IE62 protein, the primary regulatory protein of varicella-zoster virus (VZV) and the major component of the virion tegument, was an effective immunogen in the guinea pig model of VZV infection, whereas the ORF 29 gene product, a nonstructural DNA replication protein, did not elicit protection. All animals immunized with the ORF 29 protein had cell-associated viremia compared with 2 of 11 guinea pigs given the IE62 protein (P = 0.005). VZV was detected in ganglia from 38% of the animals given the ORF 29 protein and 44% of the control animals compared with 9% of the animals immunized with the IE62 protein (P = 0.04). In contrast to the IE62 protein, immunization with the ORF 29 protein did not prime the animals for an enhanced T-cell response upon challenge with infectious virus. The VZV IE62 protein has potential value as a vaccine component.

Investigation of the pathogenesis of varicella-zoster virus infection in guinea pigs by using polymerase chain reaction.

The polymerase chain reaction method (PCR) was used to investigate events in the pathogenesis of varicella-zoster virus (VZV) infection in strain 2, Hartley, and euthymic hairless guinea pigs. VZV was detected in peripheral blood mononuclear cells (PBMC) obtained 2-5 days after infection in 8 (50%) of 16 strain 2, 4 (40%) of 10 hairless, and 10 (34%) of 29 Hartley guinea pigs. The frequency of VZV-infected PBMC was estimated to be at least 1/200,000, which is comparable to that observed in human infection. When VZV PCR was used to test ganglia from hairless guinea pigs, samples from 6 of 8 animals were positive. Of 45 VZV-infected guinea pigs that were tested for cellular immunity by VZV T lymphocyte proliferation assay, 44 developed a stimulation index > 2.0. Control animals had no detectable virus by PCR and did not develop cellular immunity to VZV. These experiments showed that viremia was detectable by PCR during primary VZV infection of guinea pigs in about half of the animals regardless of the strain of guinea pig. Acquisition of cellular immunity provided a consistent marker of infection in all guinea pig strains. PCR was also useful for demonstrating VZV in guinea pig ganglia tissue, with VZV gene sequences being detectable for at least 80 days after infection. With the combination of PCR and immunologic assays, various guinea pig strains should be useful for studies of VZV pathogenesis and for the evaluation of antiviral agents and vaccine strategies.