Cutaneous abscesses are local accumulations of pus in the skin, which generally occur as a result of bacterial infections. Frequent causes are staphylococci that may either be sensitive to antibiotics (methicillin-susceptible S. aureus, MSSA) or resistant (methicillin-resistant S. aureus, MRSA) [1]. Since abscesses are poorly accessible to antibiotics [2], surgical incision and drainage of the accumulated pus are the key measures [3]. In terms of improving the outcome of surgical interventions and/or the avoidance of near-term recurrences, a meta-analysis has shown a clinical benefit of the additional oral administration of antibiotics for small, uncomplicated skin abscesses (Fig. 1) [4]. However, it remains unclear whether this benefit outweighs the risks of side effects and development of resistance – particularly because not a single case of abscess-related sepsis occurred in recent studies (n = 2,051) [3]. This warrants a critical re-evaluation of systemic antibiotic therapy.
GlobalUpdate on the antibiotic treatment of uncomplicated skin abscesses
Antibiotics increase the success of treatment and reduce recurrences
Fig. 1. Forest plot on the effect of antibiotic treatment for abscesses with respect to avoidance of failure of surgical intervention and/or recurrence [4]. (M-H = Mantel-Haenszel method; CI = confidence interval)
Resistance is not the only problem
Pale and dark forms of Ichthyol® have antibacterial activity
With that in mind, the fact that the long-established dermatological agents – locally applied sodium and ammonium bituminosulfonate – were proven to show antibacterial activity in vitro against several Gram-positive bacteria, is particularly noteworthy [5–7]. Sodium bituminosulfonate (pale Ichthyol®) showed minimal inhibitory concentrations (MIC90) of 0.25 mg/ml for MRSA, 1 mg/ml for MSSA and 0.03–0.125 mg/ml for various species of streptococci [5]. Hitherto unpublished results have since also become available [7] for ammonium bituminosulfonate (dark Ichthyol®) (Tab. 1, data on file). Triplicate determinations produced an MIC of 15.6 mg/ml for MSSA and an MIC of 7.8 mg/ml for MRSA [7] and thus demonstrated an effect even on abscesses caused by MRSA.
Tab. 1. Antimicrobial efficacy of ammonium bituminosulfonate against methicillin-susceptible (MSSA) and methicillin-resistant (MRSA) strains of S. aureus [7].
| Test concentration in culture medium preparation (n = 3) | After 24 hours | After 48 hours | After 72 hours | ||||
| MRSA | MSSA | MRSA | MSSA | MRSA | MSSA | ||
| Stock solution | 250 mg/ml | – | – | – | – | –/– | –/– |
| 1:2 dilution | 125 mg/ml | – | – | – | – | –/– | –/– |
| 1:4 dilution | 62.5mg/ml | – | – | – | – | –/– | –/– |
| 1:8 dilution | 31.25 mg/ml | – | – | – | – | –/– | –/– |
| 1:16 dilution | 15.63 mg/ml | – | – | – | – | –/– | –/– (n=2) –/(+) (n=1) |
| 1:32 dilution | 7.81 mg/ml | – | – | – | – | –/– | –/+ |
| 1:64 dilution | 3.91 mg/ml | + | – | + | – | –/+ | –/+ |
| 1:128 dilution | 1.95 mg/ml | + | + | + | + | +/+ | +/+ |
| 1:256 dilution | 0.975 mg/ml | + | + | + | + | +/+ | +/+ |
| 1:512 dilution | 0.488 mg/ml | + | + | + | + | +/+ | +/+ |
| 1:1024 dilution | 0.244 mg/ml | + | + | + | + | +/+ | +/+ |
– no visible growth detectable + visible turbidity/growth detectable –/– no visible growth detectable due to product turbidity/no growth after subculture –/+ no visible growth detectable/growth after subculture +/+ visible growth detectable in the culture medium preparations/after subculture | |||||||
Ichthyol® in self-medication
Anti-inflammatory ammonium bituminosulfonates promote maturation of the abscess and its evacuation and owing to the additional antibacterial action, are suitable for the self-treatment of abscesses – especially because no resistance to the active agent is likely to occur.
Literature
- Singer AJ, Talan DA. Management of Skin Abscesses in the Era of Methicillin-Resistant Staphylococcus aureus. N Engl J Med 2014; 370:1039–1047. doi: 10.1056/NEJMra1212788.
- Sunderkötter C, et al. Frequent bacterial skin and soft tissue infections: diagnostic signs and treatment. J Dtsch Dermatol Ges 2015;13:501–524.
- Pulia M, Fox B. Antibiotics Should Not Be Routinely Prescribed After Incision and Drainage of Uncomplicated Abscesses. Ann Emerg Med 2019;73(4):377–378. doi: 10.1016/j.annemergmed.2018.04.026.
- Wang W, Chen W, Liu Y, et al. Antibiotics for uncomplicated skin abscesses: systematic review and network meta-analysis. BMJ Open 2018;8:e020991. doi:10.1136/bmjopen-2017-020991.
- Idelevich EA, Becker K. In Vitro Activity of Sodium Bituminosulfonate: Susceptibility Data for the Revival of an Old Antimicrobial. Microbial Drug Resistance 2020;26(11):1405–1409. doi: 10.1089/mdr.2019.0390
- Pantke R. Bakteriologische Untersuchung von Arzneimitteln aus Schieferöl. Arzneim-Forsch (Drug Res) 1965;15:570–573 (in German)
- Leis W, Pacher S, et al. Prüfbericht zur Prüfung auf antimikrobielle Wirksamkeit der Wirksubstanz Ichthyol im Bouillon-Reihenverdünnungstest und Bestimmung der MHK. BioChem – Labor für biologische und chemische Analytik GmbH (unpublished) (in German)
Conflict of interest: The author declares no conflict of interest.
Disclosure: Medical writing and publication funded by Ichthyol-Gesellschaft Cordes, Hermanni & Co. (GmbH & Co.) KG.
