Contact dermatitis due to sodium colistimethate

Hypotension Following Treatment with Aerosolized Colistin in a Patient with Multidrug-Resistant Pseudomonas aeruginosa

Objective:

To report a case of a man who developed temporary hypotension after aerosolized colistin administration.

Case Summary:

A 62-year-old Arab male was admitted to the intensive care unit for respiratory failure and septic shock. Simultaneous therapy using intravenous and aerosolized colistin was initiated for the management of multidrug-resistant Pseudomonas aeruginosa. A significant but transient drop in blood pressure occurred when aerosolized colistin was introduced. However, when it was stopped, but intravenous administration was continued, no hypotension was observed. Moreover, the combined use of aerosolized amikacin with intravenous colistin did not significantly affect blood pressure.

Discussion:

It is widely accepted that aerosolization allows safe administration of colistin in the absence of significant systemic adverse effects. However, in our patient, hypotension was observed with aerosolized colistin, but not with the systemic formulation. The lack of adverse effects with administration of aerosolized amikacin in this patient demonstrates the safety of the aerosolization technique. Use of the Naranjo scale indicated a probable relationship between hypotension and aerosolized colistin administration.

Conclusions:

This case suggests that hypotension may be induced with administration of aerosolized colistin. Although this effect is rare, clinicians should be aware that hypotension may develop in critically ill patients following aerosolized colistin treatment.

Systemic colistin use in children without cystic fibrosis: a systematic review of the literature

The increasing incidence of multidrug-resistant (MDR) Gram-negative infections necessitates the use of neglected antibiotics such as colistin, even in the paediatric field. The objective of this review was to evaluate the available clinical evidence regarding the effectiveness and safety of systemic colistin in children without cystic fibrosis (CF). Relevant articles were identified from PubMed, Cochrane and Scopus databases. Ten case series and fifteen case reports, including a total of 370 children, were eligible for inclusion in this systematic review. Only 17 of the children were included in studies published after 1977. A total of 326 children received colistin for the treatment of infections and 44 for surgical prophylaxis or prophylaxis of infections in burns patients. Regarding the clinical outcome, 271 of 311 children included in the identified cases series were evaluable. From these 271 children, 235 (86.7%) were cured of the infection, 10/271 (3.7%) improved, 6/271 (2.2%) deteriorated and 20/271 (7.4%) died. Fourteen (70%) of the 20 deaths were attributed to the infection. No infection occurred in the 44 reported children with burns or surgical morbidity who received colistin for prophylaxis. Of these 44 children, 9 (20.5%) died; all deaths were attributed to co-morbidity. Nephrotoxicity occurred in 10/355 (2.8%) of the evaluable children in cases series included in this review. Most of the identified relevant case reports focused on treatment complications. The available evidence, mainly from old case series, suggests that systemic colistin is an effective and acceptably safe option for the treatment of children without CF who have MDR Gram-negative infections.

Allergic contact dermatitis from ophthalmics: 2007

We previously reviewed allergic contact dermatitis due to ophthalmic drugs and contact lens solutions. Since 1997, an additional 15 allergens have been reported. Here, we provide a review and discussion of these allergens.

Toxicity of polymyxins: a systematic review of the evidence from old and recent studies

Background

The increasing problem of multidrug-resistant Gram-negative bacteria causing severe infections and the shortage of new antibiotics to combat them has led to the re-evaluation of polymyxins. These antibiotics were discovered from different species of Bacillus polymyxa in 1947; only two of them, polymyxin B and E (colistin), have been used in clinical practice. Their effectiveness in the treatment of infections due to susceptible Gram-negative bacteria, including Pseudomonas aeruginosa and Acinetobacter baumannii, has not been generally questioned. However, their use was abandoned, except in patients with cystic fibrosis, because of concerns related to toxicity.

Methods

We reviewed old and recent evidence regarding polymyxin-induced toxicity by searching Pubmed (from 1950 until May 2005).

Results

It was reported in the old literature that the use of polymyxins was associated with considerable toxicity, mainly nephrotoxicity and neurotoxicity, including neuromuscular blockade. However, recent studies showed that the incidence of nephrotoxicity is less common and severe compared to the old studies. In addition, neurotoxic effects of polymyxins are usually mild and resolve after prompt discontinuation of the antibiotics. Furthermore, cases of neuromuscular blockade and apnea have not been reported in the recent literature.

Conclusion

New evidence shows that polymyxins have less toxicity than previously reported. The avoidance of concurrent administration of nephrotoxic and/or neurotoxic drugs, careful dosing, as well as more meticulous management of fluid and electrolyte abnormalities and use of critical care services may be some of the reasons for the discrepancy between data reported in the old and recent literature.