Vancomycin-associated shock and rash in newborn infants

Duration of vancomycin treatment for coagulase-negative Staphylococcus sepsis in very low birth weight infants

AIM

Vancomycin is widely used to treat late onset coagulase-negative Staphylococcus (CoNS) sepsis in very low birth weight (VLBW) infants. Although vancomycin is associated with a risk of toxicity and bacterial resistance, the appropriate duration of use has not been established. This study sought to investigate the association between the duration of vancomycin therapy and clinical outcome in VLBW infants with CoNS sepsis.

METHODS

The files of all VLBW infants treated for CoNS sepsis at a tertiary paediatric medical centre from 1995-2003 were reviewed for clinical data, laboratory variables and outcome. Only patients with two positive diagnostic blood cultures were included. The findings were analyzed by duration of vancomycin treatment after the last positive blood culture.

RESULTS

The study cohort included 126 infants, 48 treated for 5 days, 32 for 6-7 days, 31 for 8-10 days and 15 for >10 days. There were no differences among the groups in perinatal characteristics, central catheter dwell time, laboratory data including haematologic, renal and liver function tests, or rate of complications of prematurity. Five infants were diagnosed with infective endocarditis or aortic thrombi and were treated for >10 days. CoNS sepsis recurred in two infants (1.6%). No toxicity of vancomycin treatment was observed.

CONCLUSIONS

In VLBW infants with uncomplicated CoNS sepsis, treatment with vancomycin for 5 days after the last positive blood culture appears to be associated with a satisfactory outcome and no adverse effects. A well-controlled prospective multicentre study is needed to confirm these findings.

Antibiotics in neonatal infections: a review

The bacteria most commonly responsible for early-onset (materno-fetal) infections in neonates are group B streptococci, enterococci, Enterobacteriaceae and Listeria monocytogenes. Coagulase-negative staphylococci, particularly Staphylococcus epidermidis, are the main pathogens in late-onset (nosocomial) infections, especially in high-risk patients such as those with very low birthweight, umbilical or central venous catheters or undergoing prolonged ventilation. The primary objective of the paediatrician is to identity all potential cases of bacterial disease quickly and begin antibacterial treatment immediately after the appropriate cultures have been obtained. Combination therapy is recommended for initial empirical treatment in the neonate. In early-onset infections, an effective first-line empirical therapy is ampicillin plus an aminoglycoside (duration of treatment 10 days). An alternative is ampicillin plus a third-generation cephalosporin such as cefotaxime, a combination particularly useful in neonatal meningitis (mean duration of treatment 14 to 21 days), in patients at risk of nephrotoxicity and/or when therapeutic monitoring of aminoglycosides is not possible. Another potential substitute for the aminoglycoside is aztreonam. Triple combination therapy (such as amoxicillin plus cefotaxime and an aminoglycoside) could also be used for the first 2 to 3 days of life, followed by dual therapy after the microbiological results. In late-onset infections the combination oxacillin plus an aminoglycoside is widely recommended. However, vancomycin plus ceftazidime (+/- an aminoglycoside for the first 2 to 3 days) may be a better choice. Teicoplanin may be a substitute for vancomycin. However, the initial approach should always be modified by knowledge of the local bacterial epidemiology. After the microbiological results, treatment should be switched to narrower spectrum agents if a specific organism has been identified, and should be discontinued if cultures are negative and the neonate is in good clinical condition. Penicillins and third-generation cephalosporins are generally well tolerated in neonates. There is controversy regarding whether therapeutic drug monitoring of aminoglycosides will decrease toxicity (particularly renal damage) in neonates, and on the efficacy and safety of a single daily dose versus multiple daily doses of these drugs. Toxic effects caused by vancomycin are uncommon, but debate still exists over the need for therapeutic drug monitoring of this agent. When antibacterials are used in neonates, accurate determination of dosage is required, particularly for compounds with a low therapeutic index and in patients with renal failure. Very low birthweight infants are also particularly prone to antibacterial-induced toxicity.

Constant rate infusion of vancomycin in premature neonates: a new dosage schedule

AIMS

Since vancomycin's bactericidal action has been shown to be time-dependent, a constant rate infusion over 24 h might result in a better bactericidal efficacy. The purpose of this study was to define a new dosage schedule in prematures.

METHODS

Two vancomycin 24 h constant rate infusion schedules were tested in two groups of neonates. Postconceptional age (PCA) was 27 to 41 weeks in group 1 (n=24) and 28 to 51.5 weeks in group 2 (n=29). Group 1 neonates received continuous infusion of 10 to 30 mgkg(-1) day(-1), adjusted for PCA and weight. Group 2 was designed to take into account the significant relationship observed in group 1 between vancomycin clearance standardized on weight and PCA and consisted of a constant loading dose of 7 mg kg(-1) followed by continuous infusion of 10 to 40 mg kg(-1) day(-1) adjusted for PCA and weight.

RESULTS

Mean vancomycin serum concentration at steady state was 11+/-3.1 mg1(-1) in group 1 and 15.4+/-6.2 mg1(-1) in group 2. Fifty-six percent of group 1 values vs 88% of group 2 values were between 10 and 30 mg at steady state (P<0.01). Both regimens were well tolerated.

CONCLUSIONS

A loading dose of vancomycin followed by constant rate infusion of the appropriate dose adjusted for PCA and weight might improve vancomycin concentrations in neonates.

Comparative safety of teicoplanin and vancomycin

Teicoplanin have different safety profiles which can affect choice. Nephrotoxicity is significantly less likely to occur during treatment with teicoplanin than vancomycin when an aminoglycoside is being given concurrently. 'Red man' syndrome is a troublesome effect of vancomycin infusion which is extremely uncommon with teicoplanin use. Rash and fever can be dose-related phenomena but patients reacting to one glycopeptide may not react to both. Although thrombocytopenia is more frequent with teicoplanin, it is reversible and seldom seen at standard doses.

[Vancomycin and cardiac arrest in the infant]

BACKGROUND

Different adverse effects induced by vancomycin bolus infusion are described, but cardiac arrest seems rare, in children as in adults.

CASE REPORT

Two infants, 5 and 12 months old, were admitted after cardiac arrest, following vancomycin bolus infusion in excessive dose. They recovered after prompt resuscitation and their short term follow-up was normal.

CONCLUSION

Two mechanisms are invoked: anaphylactic shock and direct cardiovascular toxicity. Both are dose- and infusion rate-dependent, and probably intersubject dependent. Usually, cardiac arrest is promptly reversed by adequate resuscitation. The rules of prescription are: adequate dilution and slow rate of infusion. If any adverse effect occurred, preventive antihistaminic drug therapy should be advised.

Comparison of vancomycin and teicoplanin for prophylaxis of sepsis with coagulase negative staphylococci (CONS) in very low birth weight (VLBW) infants

A prospective randomized study was performed to evaluate the efficacy of a low dose (5 mg/kg/day bid) vancomycin compared with a low dose (5 mg/kg/day once daily) teicoplanin therapy to prevent CONS sepsis in VLBW-infants. All infants received this therapy after their 4th day of life or after an eventual therapy of early onset sepsis as long as an i.v. line was in place or 1500 g body weight. Twenty-seven infants were treated with vancomycin (birth weight 1103 +/- 286 g, gest. age 28.8 +/- 1.9 weeks), 28 with teicoplanin (birth weight 1133 +/- 226 g, gest. age 29.04 +/- 2.2 weeks). The infants were observed for clinical and laboratory signs of sepsis. On day 4 of therapy and every 3rd day during therapy serum creatinine levels, tracheal aspirates, stool cultures and vancomycin/teicoplanin peak and trough levels were obtained. We could not detect any case of blood culture positive sepsis and 1 case of suspected sepsis (neg. blood cultures) in both groups, as compared with a former CONS sepsis rate of 24% in our institution's VLBW infants without antibiotic prophylaxis. Nine patients in the vancomycin and five in the teicoplanin group had tracheal colonization with CONS. In both groups peak and trough levels of antibiotics were in the bactericidal range. Serum creatinine was not normal in both groups. We conclude that teicoplanin is preventing CONS sepsis as well is vancomycin. The minimal inhibitory concentrations of both antibiotics against grampositive isolates in units using this strategy have to be observed carefully to detect emerging resistance.

A review of the Redman syndrome and rifampicin overdosage

The literature was reviewed for cases of cutaneous pigmentation induced by rifampicin overdosage. 29 examples have been described, in which 2 general groups of individuals were observed. The first consisted of older individuals (average age 27.1 years) who attempted suicide. A prior history of suicide attempts, depression and substance abuse was a predominant factor in these patients. The second group included generally younger patients (average age 2.9 years) in whom misformulation of rifampicin preparations for treatment of Haemophilus influenzae Type B resulted in bright reddish-orange discoloration to the skin. The time to clinical appearance of skin discoloration was approximately 2.2 hours after administration. Periorbital or facial oedema occurred in 72.4% of the patients, pruritus in 62.1% and either nausea, vomiting or diffuse abdominal tenderness in 51.7%. Limited laboratory data are available but these indicate that all patients had elevated levels of total bilirubin. Histological examination in selected individuals revealed rifampicin crystal deposits in the nasopharynx, gastrointestinal tract and lining of the aorta. In adults, it appears that a dose of at least 14 g of rifampicin is necessary before cardiovascular-pulmonary arrest occurs. Other than general supportive measures, very few methods are described in the literature for the treatment of acute intoxications with this drug. A differential diagnosis of other causes of reddish-orange pigmentation is discussed, together with clinical information to differentiate these cases from toxic rifampicin ingestion.

"Red man syndrome" with vancomycin: report of case

Vancomycin is a recommended alternative prophylactic antibiotic for penicillin-allergic patients with prosthetic mitral valves. During the course of recommended treatment, a drug reaction known as "red man syndrome" was encountered. Because vancomycin is appropriate for some dental situations, the general practitioner should be acquainted with its use and possible side effects.