A Retrospective Chart Review of Inflamed Epidermal Inclusion Cysts

BACKGROUND

Epidermal inclusion cysts (EIC) are one of the most common forms of cysts found on and/or underneath the skin. Inflamed EICs typically show signs and symptoms such as pain and erythema, mimicking cutaneous abscess. However, prior studies have demonstrated at least 20% of lesions are culture negative.

OBJECTIVE

To determine the rate of culture positivity in mild inflamed epidermal inclusion cysts, in particular to identify whether empiric antibiotics are warranted.

METHODS

In a retrospective chart review 76 cases of inflamed EIC that were mild (lacking systemic symptoms) were analyzed who presented to the department of dermatology at Mount Sinai between 2016–2019.

RESULTS

Of cultures taken from inflamed cysts, 47% resulted in no bacterial growth or growth of normal flora, 38.4% resulted in growth of aerobic bacteria with methicillin-resistant Staphylococcus aureus (8%), Staphylococcus lugdunensis (5%), and methicillin-sensitive Staphylococcus aureus (13%) predominating, and 9.3% resulting in growth of anaerobic bacteria with Finegoldia magna, Peptostreptococcus, and Cutibacterium acnes presenting. Review of prescribed treatment regimens often involved antibiotic medication, despite a high prevalence of negative culture.

CONCLUSIONS

Almost half of cases of mild inflamed EIC (lacking systemic symptoms) cultured will not grow pathogenic bacteria, therefore incision and drainage with culture and appropriate therapy is a viable therapeutic option in uncomplicated inflamed EIC lesions. In this way, over prescription of antibiotics can be minimized. J Drugs Dermatol. 2021;20(2):199-202. doi:10.36849/JDD.5014.

IL-1 Receptor-Knockout Mice Develop Epidermal Cysts and Show an Altered Innate Immune Response after Exposure to UVB Radiation

In this study, we observed that mice lacking the IL-1 receptor (IL-1R) (IL1r^-/-) or deficient in IL1-β developed multiple epidermal cysts after chronic UVB exposure. Cysts that developed in IL1r^-/- mice were characterized by the presence of the hair follicle marker Sox 9, keratins 10 and 14, and normal melanocyte distribution and retinoid X receptor-α expression. The increased incidence of cysts in IL1r^-/- mice was associated with less skin inflammation as characterized by decreased recruitment of macrophages, and their skin also maintained epidermal barrier function compared with wild-type mice. Transcriptional analysis of the skin of IL1r^-/- mice after UVB exposure showed decreased gene expression of proinflammatory cytokines such as tumor necrosis factor-α and IL-6. In vitro, primary keratinocytes derived from IL1r^-/- mice were more resistant to UVB-triggered cell death compared with wild-type cells, and tumor necrosis factor-α release was completely blocked in the absence of IL-1R. These observations illustrate an unexpected yet prominent phenotype associated with the lack of IL-1R signaling in mice and support further investigation into the role of IL-1 ligands in epidermal repair and innate immune response after damaging UVB exposure.

Giant epidermoid cyst of the spleen with carbohydrate and cancer antigen production managed laparoscopically

True cysts of the spleen are rare; in a few cases, high serum levels of carbohydrate and cancer antigen have been reported. In such instances, cyst resection or splenectomy is indicated to rule out malignant lesions and to remove the cancer antigen producing epithelium. We report the case of a young woman with a symptomatic giant epidermoid cyst of the spleen. Due to the secreting epithelium lining the cyst, serum levels of CA 19-9 and CA 125 were elevated. Laparoscopic splenectomy achieved symptoms relief and and long-term normalization of serum tumor markers.

Median raphe cyst in the scrotum, mimicking a serous borderline tumor, associated with cryptorchidism after orchiopecxy

Median raphe cyst (MRC) is a benign lesion occurring predominantly in the ventral surface of the penises of young men and is an embryological developmental anomaly of the male genitalia. Serous borderline tumors (SBT) are found most frequently in the female ovary and only several cases with SBT of the male genitalia have been reported. We describe a case of MRC with features of SBT, which appeared in the scrotum of a 9-year-old boy after orchiopexy and was associated with surgery for cryptorchidism. The cyst arose on the right testicular tunica and consisted of cystic components with intracystic papillae lined by stratified epithelial cells, some of which showed mild cytological atypia and sporadic mitosis. These epithelial cells expressed CA 125, CA 19-9, carcinoembryonic antigen, estrogen receptor and progesterone receptor. Although no cases of MRC with characteristics of SBT in association with the rete testis has been described, the current report gives additional information for follow-up of cryptorchidism.

Cutaneous ciliated cyst of the lower limb in a male

Cutaneous ciliated cysts of the lower limb are rare. Almost exclusively occurring in women they have been widely regarded as Müllerian heterotopias. A second case in a man is reported, the literature reviewed and the origin of this lesion briefly discussed.

Histocompatibility locus antigens (HLA) in the epidermoid type of lung carcinoma

HLA-A and B antigens were determined in a study of 162 patients (93 epidermoid type, 20 adenocarcinoma, 26 small-cell carcinoma and 23 undifferentiated types) with lung cancer. Differences between antigen frequencies in cancer and control populations were studied by chi 2Y analysis or Fisher's exact test. Survival data were analyzed using Cox's model for censored data. Cancer patients had a decreased frequency of the antigen HLA-B40 (chi 2Y = 14.15, P = 0.00018, Pc = 0.003, relative risk = 0.21). Patients with HLA-A10, A 11 and B27 had a shortened mean survival time. Patients with HLA-B12 had a prolonged survival time.

[Detection of papillomavirus common antigens in plantar epidermoid cysts]

A total of 23 cases of human papillomavirus-associated epidermoid cysts, including one presented here, have been reported in Japan. A review of the literature revealed that the appearance of eosinophilic intracellular substances and that of vacuolar substances in the horny layer of cysts characterize these cases. High detection of human papillomavirus, the pathological features in these cases, and the observation of our case from the onset in which verrucous lesions had preceded a cyst may favor the possibility that HPV would directly produce cysts in these cases.

Papillomavirus antigen in the epidermoid cyst of the sole. Immunohistochemical and ultrastructural study

An epidermoid cyst of the sole was studied immunohistochemically and ultrastructurally. Papillomavirus particles were present in the horny layer and in the upper layers of the epidermis of the cyst and within the acrosyringeal epithelium overlying the cyst. Thickened basal lamina-like structures similar to those found in the eccrine sweat duct tumors such as in cylindroma and eccrine spiroadenoma existed at the epidermal-dermal junction of the cyst wall. Carcinoembryonic antigen was immunohistochemically demonstrated in the center of the epidermoid cyst and the DAB reaction products took the shape of a circle resembling that of the sweat ducts in the horny layer.

Analysis of the proinflammatory property of epidermal cyst contents: chemotactic C5a anaphylatoxin generation

We investigated in vitro the contents of epidermal cysts for complement activation and found that they activated complement mainly through the alternative pathway. Chemotactic C5a anaphylatoxin produced by the cyst contents after contact with serum most likely plays a significant role in the initiation and aggravation of inflammation in ruptured epidermal cysts. Our additional study disclosed that components of three representative follicular resident microorganisms (Pityrosporum ovale, Propionibacterium acnes, and Staphylococcus epidermidis) also produced C5a anaphylatoxin mainly through the alternative pathway; the C5a production was more vigorous than that by a virulent pathogen, Staphylococcus aureus. These results suggest that accidental colonization of the cyst contents by these follicular microbial flora further augments the inflammatory changes in ruptured epidermal cysts.

Leukocyte chemotactic properties of soluble horny contents in epidermal cysts

Epidermal cysts are one of the most common tumors of the skin. Although asymptomatic ordinarily, they may sometimes become severely inflamed with massive invasion of polymorphonuclear leukocytes (PMN). We studied in vitro PMN chemotactic properties of the aqueous extract prepared from the horny material of epidermal cysts obtained from three patients. A crude aqueous extract of the horny content of the cysts showed PMN chemotactic activity, which, however, was less than that of a horny layer extract prepared from normal skin. Characterization of PMN chemotactic activity using a Sephadex G-75 column showed a peak in the low molecular weight fractions eluting between the vitamin B12 and phenol red markers, which corresponds with the peak of absorbance at 280 nm. The chemotactic substances withstood boiling and trypsin or protease digestion. Although the chemotactic activity was partially ether-extractable, the presence of leukotriene B4 was not demonstrated by radioimmunoassay. In addition to their own chemotactic activity, the horny extracts of epidermal cysts showed cytotaxigenic properties in the presence of fresh serum.

Absence of human leukocyte antigen molecules in skin tumors and some cutaneous appendages: evidence using monoclonal antibodies

Four highly sensitive monoclonal antibodies were assessed for their use in an immunoperoxidase technic on cutaneous sections. Three, B2, C23, and 2A1, were found to discriminate basal cell carcinomas (BCCs) from benign proliferative disorders of skin, and 2A1, a monoclonal antibody against the heavy chain component of class 1 human leukocyte antigens (HLA) for the first time directly demonstrated the absence of this structure from the malignant cell membrane. However, the deeper portions of hair follicles were also found to be unlabeled, and further study of benign follicular tumors which may histologically mimic basal cell carcinomas is suggested.

Lymphocyte transformation in subjects with nodulo cystic acne

Patients with severe nodulo-cystic acne are known to have elevated serum antibody levels and increased immediate hypersensitivity reactions to Propionibacterium acnes. This organism is the predominant bacterium in normal pilosebaceous follicles of human skin, and can be consistently isolated from pustular lesions in acne. Previously it had been observed that delayed cutaneous hypersensitivity reactions to P. acnes were negative in patients with acne. The present study investigated the proliferative response of lymphocytes from patients with nodulo-cystic acne to phytohaemagglutinin (PHA) and P. acnes antigen stimulation. The response to PHA stimulation was within normal limits. The response to P. acnes antigen showed a significant increase over control values obtained by testing lymphocytes from acne-free subjects. Thus cell mediated immunity to P. acnes may be present in subjects with severe inflammatory acne. These findings raise the possibility that reactions to P. acnes may contribute to intensifying the inflammatory response in acne lesions.