Furuncles and Carbuncles in Darker Skin

00:02 Welcome to our lecture on Furuncles and Carbuncles.

00:07 What is a furuncle ? The other lay term language for uncle is a boil.

00:11 It's deep infection of a hair follicle.

00:14 And a carbuncle, on the other hand, is clusters of furuncles that are subcutaneously connected.

00:20 So furuncle, it's one boil, and carbuncle is a combination of boils. And this tends to occur deep down in the follicle.

00:30 It's common in adolescence and early adult life, and carbuncles are relatively rare compared to fair angles.

00:38 What are some of the risk factors? Obesity, immunodeficiency, for example, patients who have HIV infection , AIDS, or are on chemotherapy for malignancy and older people. Diabetes mellitus is also a predisposing factor for carbuncles of our ankles.

00:56 Of course smoking and low hemoglobin anemia.

01:00 So what are the etiological agents of these two conditions, it's usually due to staph aureus.

01:07 And of course, methicillin resistant staph aureus is a common finding. Which areas are affected in patients with furuncles or carbuncles: the face, the neck, the axillae, and the buttocks. Now let's focus on the ankle.

01:26 How do we describe it? Clinically, it's a tender red perifollicular swelling, which can lead to a pustule that discharge necrotic tissue and pus.

01:37 And remember, in dark skin, you may not actually appreciate the erythema, or the redness, may lead to a permanent scar after healing. And then again in black patients you may even get post-inflammatory hyperpigmentation that we spoke about.

01:53 So we spoke about the furuncle.

01:56 Now let's move on and talk about furunculosis .

02:00 It's acute and recurrent appearance of multiple furuncles on multiple skin sites. So now you can differentiate between a furuncle, furunculosis and now we're moving on to the third type the carbuncle.

02:15 So how do we define a carbuncle.

02:17 It's a hard, painful red lump about 3 to 10cm in diameter. You can get suppuration, which is pus that is discharged from the multiple follicular orifices.

02:31 It may be associated with malaise, fever, lymphangitis that is inflammation of your lymphatic vessels, and lymphadenitis, which is inflammation and painful lymph nodes.

02:44 The complications include abscesses, cellulitis, post-inflammatory hyperpigmentation, which is unique to dark skin.

02:52 So how do we diagnose these conditions? The clinical history and physical examination findings are important.

03:00 As we have described, a password for microbiological examination is prudent. And this should be sent for microscopy culture and sensitivity. And now looking at the differential diagnosis.

03:14 One of the differential diagnoses is superficial staphylococcal folliculitis.

03:19 Perifollicular swelling not seen unlike in furuncle and carbuncle. The second one is a ruptured epidermoid cyst, which is a sterile, purulent, keratinous material that is seen coming out of an epidermoid cyst.

03:37 You can also confuse it with pharyngula meiosis, but usually here you see larva, but this is not commonly seen.

03:46 Management of these conditions involve incision and drainage of an abscess. Usually MRSA effective antibiotics are recommended as well.

04:00 The antibiotics that are effective against MRSA are tetracyclines and trimethoprim sulfamethoxazole.