An unusual dark macular lesion in the plantar region of a child

A 7-year-old male patient from Bonito (Mato Grosso do Sul State, Brazil) presented “dark spots" on his foot without previous manifestation (Figure A). Frightened by the tonality of the lesions, his mother sought medical care. The lesions disappeared after two months.

FIGURE A:
Left: Hyperchromic macules in the calcanum region after three days and after one month. Right: Millipede (Diplopoda) in movement and in the defense position.

Skin lesions caused by Diplopoda or millipedes (“piolhos-de-cobra”, embuás, gongolôs) are relatively common and occur when these myriapods penetrate the shoes and are compressed or crushed^1,2. At this time, they release toxic substances, such as alkaloids and hydrogen cyanide, which cause moderate initial inflammation and long lasting hyperchromic pigmentation. This can lead to complex differential diagnoses, especially when located in the extremities of the elderly and diabetics, as they simulate arterial ischemia and necrosis. The macules of the patients are anomalous and the circular and concentric aspect reproduces the body shape of the animal curled up and justifies the publication³.

Ethical comments

The Ethics Committee of the Botucatu Medical School does not ask for authorization to publish isolated case reports.

ACKNOWLEDGMENTS

We acknowledge the collaboration of Mrs. Liliam Ferrarezi for the assignment of the images used.

REFERENCES

• ¹
  Haddad Jr V, Cardoso JLC, Rotta O, Eterovic A. Acidentes provocados por Millipede com manifestações dermatológicas: relato de dois casos. An Bras Dermatol. 2000;75: 471-4.
• ²
  Cardoso JLC, França FOS, Hui FH, Malaque CMS, Haddad Jr V. Animais peçonhentos no Brasil: biologia, clínica e terapêutica dos acidentes. São Paulo: Editora Sarvier; 2003. p. 258-64.
• ³
  Lima CAJ, Magela A, Talhari S, Cardoso JLC, Oliveira FGM, Haddad Jr V. Exogenous pigmentation in toes feigning ischemia of the extremities: a diagnostic challenge brought by arthropods of the Diplopoda Class (“Millipedes”). An Bras Dermatol . 2010;85(3):391-2.

Publication Dates

• Publication in this collection
  18 July 2019
• Date of issue
  2019

History

• Received
  07 Jan 2019
• Accepted
  26 Mar 2019