bubble_chart Overview

Ariboflavinosis is a syndrome caused by a deficiency or insufficiency of riboflavin in the body, primarily manifested by scrotal inflammation, cheilitis, glossitis, and angular stomatitis.

bubble_chart Etiology

Riboflavin is an essential component of the yellow protein coenzyme required for normal intracellular oxidation and reduction, and is closely related to the metabolism of fats, sugars, and proteins. The storage of riboflavin in tissues is limited and is quickly depleted. The estimated daily nutritional requirement for humans is 0.6mg/4186.8J (1000 kcal). Deficiency can cause a series of damages in experimental animals, but in humans, the effects are milder, primarily causing skin and mucous {|###|} membrane damage.

The causes of riboflavin deficiency may include:

1. Insufficient dietary supply;
2. Sudden changes in dietary habits or improper cooking and consumption methods;
3. Pregnancy, heavy physical labor, etc., leading to increased consumption without a corresponding increase in riboflavin intake;
4. Gastrointestinal diseases, hyperthyroidism, advanced stage cancer, chronic ethanol intoxication, fever, and chronic wasting diseases, which affect riboflavin absorption or increase its demand;
5. Oral contraceptives and other medications, particularly phenazine derivatives, tricyclic antidepressants, boric acid, etc., which may interfere with riboflavin metabolism or interact with riboflavin, leading to deficiency.

bubble_chart Clinical Manifestations

The individual symptoms of riboflavin deficiency disease are not specific, but when observed collectively, they can suggest the diagnosis. These symptoms mainly include scrotal inflammation, glossitis, cheilitis, and angular stomatitis.

(1) Scrotal inflammation is the earliest and most common manifestation, which can be divided into erythematous, papular, and eczematous types.

1. Erythematous type: The most common, initially presenting as light red patches symmetrically distributed on both sides of the scrotum, with bright red edges. Later, the surface becomes covered with shiny, adherent, grayish-white or brown scales. In severe cases, the edges may have thick, dark brown crusts. Removing the scales reveals a tender base without infiltration.
2. Papular type: Initially, there are scattered groups of needle-sized to soybean-sized flat, round papules covered with thin brown crusts, which may also merge into patches. Early lesions may appear on one side only, while advanced stages show symmetrical distribution on both sides of the scrotum.
3. Eczematous type: The scrotum shows localized or diffuse infiltration, thickening, and lichenification, similar to chronic eczema. There may be exudation, crusting, and occasionally rhagades, with a chronic course. In long-standing cases, the lesions may extend to the penile shaft or the inner thighs.

In addition to scrotal lesions, similar seborrheic dermatitis-like oily scaly lesions may occur on the central face, nasolabial folds, nasal wings, inner and outer canthi of the eyelids, and earlobes.

(2) Glossitis: Early stages show fungiform papillae the size of needle tips and circumvallate papillae the size of soybeans with thickened papules. The middle of the tongue exhibits sharply demarcated erythema, wide at the front and narrow at the back, resembling a bottle gourd peel. In severe cases, the entire tongue may appear cyanotic and significantly swollen. Later, the papillae shrink or disappear, and the tongue surface becomes smooth and atrophic, with fissures of varying sizes and depths, accompanied by pain.

(3) Cheilitis: Primarily affects the lower lip, presenting as dryness, scaling, and pigmentation. Occasionally, there may be erythema, erosion, and vertical fissures.

(4) Angular stomatitis: The corners of the mouth become macerated, whitish, eroded, with rhagades and crusting, prone to infection, and may scar after healing.

Other mucosal symptoms include photophobia, tearing, conjunctivitis, superficial keratitis, corneal opacities or even ulcers, crusting in the nasal vestibule, rhagades, etc.

bubble_chart Diagnosis

The diagnosis is not difficult based on clinical features such as scrotitis and glossitis, combined with dietary history. If in doubt, a trial treatment for a few days can confirm the diagnosis, and blood riboflavin levels can be measured if necessary.
Adjust dietary habits, improve cooking techniques, and provide a diet rich in riboflavin, such as milk, meat, liver, eggs, and vegetables. Riboflavin 5–20 mg/day. Local symptomatic treatment.

bubble_chart Treatment Measures

Adjust dietary habits, improve cooking techniques, and provide a diet rich in riboflavin, such as milk, meat, liver, eggs, and vegetables. Riboflavin 5–20 mg/day. Local symptomatic treatment.