Introduction
Mastitis refers to infection of the breast due to invasion of bacteria into mammary glands and lactiferous ducts. This problem is frequently encountered among women with breastfeeding, especially primipara. It usually occurs 3 - 4 weeks after labor due to rupture of nipple and invasion of bacteria complicated by unsmooth secretion of milk and stagnation of milk. The clinical manifestations are local swelling, pain, tenderness and hard nodules of the breast, accompanied by aversion to cold, fever and enlargement of lymph nodes over the armpit on the affected side. This disease pertains to breast abscess in TCM due to invasion of pathogenic factors or accumulation of milk; or due to mental upsets and stagnation of liver qi; or due to excessive intake of rich foods and accumulation of heat in the stomach meridian that lead to the obstruction of the vessels and stagnation of qi, blood and milk.

Syndrome differentiation
Redness, swelling and pain of the breast on the affected side; breast nodules, swelling, pain and difficulty in secreting milk before suppuration; frequently accompanied by headache due to cold and heat, nausea and thirst; enlargement of the breast lumps, redness and swelling of skin, local continuous throbbing pain and lingering fever.

Treatment
Prescription: Zusanli (ST 36), Shaoze (SI 1) and Jianjing (GB 21).
Modification: For headache due to cold and heat, Hegu (LI 4), Quchi (LI 11) and Fengchi (GB 20) are added; for distension and pain of the breast, Qimen (LR 14) and Taichong (LR 3) are added; for chest oppression and hiccup, Neiguan (PC 6) and Tanzhong (CV 17) are added.

Performance: Reducing needling technique is used. Fengchi (GB 20) and the acupoints on the chest and back are needled with rotating manipulation. Shaoze (SI 1) is pricked to let blood. Jianjing (GB 21) is needled 0.3 - 0.5 cun lest the viscera be impaired. Qimen (LR 14) is needled 0.5 cun obliquely toward the breast. Tanzhong (CV 17) is needled horizontally 1 cun toward the affected part. The needles are retained for 30 minutes and manipulated at intervals.