Question

Patient is a 10-year-old male ,good health. Felt pain in his left calf at lunchtime despite not being injured.

Ingrown hair in the location of the pain. That evening small amount of pus from the ingrown hair.

Next morning, found cellulitis on the calf and more pus. By the afternoon, the area of the cellulitis had grown significantly and the patient rushed to the medical center.

Vital signs measured, including pulse, respiration, blood pressure and temperature. All the signs were within the normal limits.

Physical examination of calf, which was red and warm to the touch but with no area of obvious fluctuance. No lymphadenopathy was observed. The physician punctured the central area of the cellulitis, near the area that the patient indicated was the ingrown hair, three times with a 20-gauge needle but no pus was drained. The patient was referred to surgery service and the surgeon gave him 2 g of ceftriaxone intramuscularly and started him on oral cephalexin. The patient returned to the medical center 48h later with obvious area of fluctuance in the centre of the cellulitis area and reported low-grade fever during the past 48 hours. It was obvious that pus is present.

3. What could be the source of the infection?

Answer 1

Cellulitis is a bacterial infection caused by redness of the affected area and warmth and tender on touch. It mainly affects the skin of lower leg but can also affects other tissues as well. Initial symptoms includes pain and tenderness of the affected area, redness or inflammation, a feeling of warmth in the affected areas, pus formation, skin sore or rash. It is caused by bacterial infections like Staphylococcus and Streptococcus strains which enter inside the body by cuts, wounds or crack in the skin. The skin injuries like cut, bug bites or surgical wounds may serve as source of infection.

On treatment of the above patient while puncturing the central area of the cellulitis, it was observed that no pus was drained. The indication of having abscess, which is the accumulated pus underneath the skin was confirmed by referring the patient to surgery service where he was administered with 2g of ceftriaxone intramuscularly and oral cephalexin in order to diagnosed the pus that might remain underneath the skin. After 2 days of administering the drugs there was observed fluctuance in the central area of the cellulitis with low grade fever. This suggest the presence of pus which was initially not fluctuant and neither it shown the sign of lump. The abscess or pus remaining inside symptomise fever, fluctuance of the affected area because it was initially penetrated deep inside the tissues of skin, so the pus need to be drained out as its presence may lead to further complications. The symptoms of cellulitis may mimics other skin related disorder like Erysipelas. But it can be differentiated as cellulitis rash has a raised border and it also feel hot to touch.

So, the source of infection might be from cut or wound resulting in crack in skin which serves as the entry point of bacterians like Staphylococcus and Streptococcus.