Blood, blood-forming organs – immune system (D50-D90).
- Iron deficiency anemia (anemia due to iron deficiency) – Note: In generalized pruritus, iron deficiency is present in up to 40% of cases.
Endocrine, nutritional and metabolic diseases (E00-E90).
- Diabetes mellitus (diabetes).
- Food intolerances
Skin and subcutaneous (L00-L99)
- Allergic contact dermatitis (contact allergy) – due toe.g. dyes on printed toilet paper, wet wipes with fragrances and preservatives, soaps, etc.; common contact allergens are benzocaine, cinchocaine, lidocaine or fragrances as often found in wet toilet paper, skin care or disinfectants
- Atopic eczema (neurodermatitis)
- Decubitus – refers to an ulcer (ulcer) of the skin or mucous membrane, which is caused by prolonged exposure to pressure (eg, wheelchair users).
- Epidermal cyst – bulging elastic node, which is filled with horny masses.
- Hidradenitis (inflammation of apocrine sweat glands) – especially in the pubic area and armpit.
- Idiopathic pruritus ani (with unknown cause).
- Lichen sclerosus et atrophicus – rare, chronic inflammatory progressive connective tissue disease that is probably one of the autoimmune diseases; 4% of women with lichen sclerosus develop vulvar carcinoma (vulvar cancer; cancer of the female external genital organs)
- Psoriasis (psoriasis)
- Psoriasis inversa, a form of psoriasis vulgaris
- Sinus pilonidalis (coccygeal fistula; inflammatory fistulas that almost always occur above the rima ani (buttock crease); attributed to the ingrowth of broken hairs into the skin).
Infectious and parasitic diseases (A00-B99).
- Candida albicans
- Chlamydial infection – most common bacterial agent of urogenital infections (infectious diseases affecting the urinary tract and/or reproductive organs).
- Erythrasma (dwarf lichen; Corynebacterium minutissimum).
- Gonorrhea (gonorrhea; venereal disease).
- Herpes simplex viruses HSV-1/-2
- Mycoses (fungal diseases) – especially dermatophytoses (Candia albicans); especially common in diabetics and after systemic therapy with antibiotics or steroids.
- Nematodes (threadworms)
- Perianal streptococcal infections//perianal streptococcal dermatitis (PSD) (in children) – symptoms/discomfort: perianal itching, soreness, and pain; causative agent: β-hemolytic streptococci (BHS); treatment of choice: oral antibiotics with penicillins or cephalosporins.
- Perianal warts (condylomata acuminata; synonyms: genital warts, wet warts and genital warts) caused by HPV viruses (HPV 6 and 11).
- Staphylococcus aureus
- Syphilis (lues; venereal disease)
- Tinea analis – dermatophyte infection, mostly Trichophyton rubrum is involved.
- Worm infestation (oxyuriasis); mostly diagnosed in children; typically severe itching almost exclusively at night.
Mouth, esophagus (esophagus), stomach and intestines (K00-K67; K90-K93).
- Anal fissure – painful tearing of the mucous membrane at the anus.
- Anal fistula – inflammatory altered ducts (fistulas) in the anal region (anus region).
- Anal marisques – sagging skin folds (marisques) around the external anus.
- Diarrhea (diarrhea), chronic or recurrent.
- Hemorrhoids
- Crohn’s disease – chronic inflammatory bowel disease; it usually progresses in episodes and can affect the entire digestive tract; characteristic is the segmental affection of the intestinal mucosa (intestinal mucosa), that is, several intestinal segments may be affected, which are separated by healthy sections; possibly anal or perianal fistulas.
- Perianal abscess – encapsulated collection of pus, which is located in the area of the anus.
- Psychogenic pruritus ani (eg, due toanxiety, depression, stress).
- Rectal prolapse (rectal prolapse).
- Rectovaginal fistula – pathological connecting duct between the rectum and vagina.
Neoplasms – tumor diseases (C00-D48)
- Anal intraepithelial neoplasia (AIN) due to HPV high-risk types (especially HPV type 16); risk factors: smoking, immunodeficiency, previous condylomata acuminata → anal carcinoma.
- Anorectal carcinoma – malignant neoplasm in the area of the anus and rectum.
- Bowen’s disease – skin disease, which belongs to the precancerous (precancerous).
Symptoms and abnormal clinical and laboratory findings not elsewhere classified (R00-R99)
- Fecal incontinence – inability to retain bowel movements.
Injuries, poisonings, and other consequences of external causes (S00-T98).
- Trauma (injury) from foreign bodies, sexual practices, etc.
- Perianal hematoma – bruise around the anus.
Medication
- Drug intolerances
Other causes
- Diet
- Hot spices
- Lack of anal hygiene or excessive anal hygiene.
- Chemical irritation by spicy meal, lubricants, soaps, etc.
- Wearing tight-fitting, non-breathable underwear.
- Use of externals:
- Shower gel
- Wet wipes
- Soaps
- Toilet paper
- Perineal piercing
