Foot infection gram-negativeL08.8

Acute, exudative inflammation of the forefoot, including the interdigital space between the toes, caused by Gram-negative germs (often mixed infections). Bacterial infection mostly in the warm season on the floor of a pre-existing tinea pedis.

Gram-negative bacteria, especially Pseudomonas aeruginosa or Proteus mirabilis. Often grafted onto a fungal infection (so-called mixed foot infection). Hyperhidrosis and occlusive footwear have a beneficial effect.

Often hyperhidrosis, wearing tight shoes. Usually preceded by an insufficiently pre-treated tinea pedis (the usual antimycotics have a "gram-negative gap".

interdigital space between the toes, spreading to the adjacent toe areas and the forefoot

Mostly extensive, painful erosions or ulcerations of the interdigital spaces, the adjacent parts of the toes and the dorsum of the foot. Pronounced collateral oedema and deep reddening of the affected areas; severe oozing of the lesional (dripping wet) areas. Extensive maceration of the adjacent skin areas. Penetrating, sweetish foul odour. Painful lymphadenitis.

• Broad-spectrum antibiotics. In gram-negative foot infections, the germ Pseudomonas, which is frequently involved, is increasingly resistant to the common preparations Levofloxacin (e.g. Tavanic) 1-2 times/day 500 mg p.o. and Ciprofloxacin (e.g. Ciprobay) 2 times/day 250-500 mg p.o, the following antibiotics are now recommended: Piperacillin (e.g. Piperacillin-ratiopharm) 3-4 times/day 2-4 g i.v.), Ceftazidim (e.g. Fortum) 2-3 times/day 1-2 g i.v.
• Imipenem/cilastatin (e.g. Zienam) 3 times/day 1 g i.v. is reserved for severe infections as a reserve antibiotic.

1 Weidner et al (2017) Gram-negative bacterial toe web infection - a systematic review. J Eur Acad Dermatol Venereol 32:39-47