凡十六岁以上为成人，病则为痨，十六岁以下为小儿，病则为疳。缘所禀之气血虚弱，真元不足，脏腑娇嫩，
易于受伤，有因一岁以内，肠胃未坚，乳食杂进，所吮之乳，与所食之物，不相融化而成者；有因儿仅岁余，甘
肥无节，积滞日久，面黄肌削，而成者；有因二三岁后，杂物恣其啖食，食久成积，又因取积太过，反伤胃气而
成者；有因大病之后，吐泻疟痢，乳食减少，以致脾胃失养而成者；有因乳母寒热不调，或喜怒房劳之后，即与
乳哺而成者。究其病源，莫不由于脾胃。盖胃为水谷之海，水谷之精气为营，悍气为卫，营卫丰盈，灌溉五脏，
所以气足毛孔致密，腠理坚强，血足则颜色鲜妍，皮肤润泽，若病疳之形不魁，乃气不足也，病疳之色不华，又
血不足也，而要皆由脾胃之因积化热，因热成疳，消耗气血，煎熬津液，其证初起，不过尿如米泔，午后潮热，
历久失治，则转为头皮光急，毛发焦稀，腮缩鼻干，口馋唇白，两眼昏烂，操眉擦鼻，脊耸体黄，斗牙咬甲，焦
渴自汗，便白泻酸，肚大青筋，酷嗜瓜果咸炭水泥者，即疳之正候也。若谓治疳必攻其积，然积为虚中之积，恐攻
不受攻，而疳危矣。若谓治疳必除其热，然热为虚中之热，恐除未尽除，而疳又危矣。苟能分其所属而善治之，
何至有恶食滑泻，乳食直下，牙龈黑烂，头项软倒，四肢厥冷，下痢肿胀，面色如银，肚硬如石，肌肉青黑，肛
门如筒，口吐黑血，吐痢蛔虫，种种不治之危候乎，故不厌烦辞而为之解。
凡是年满十六岁的人称为成人，患病则称为“痨”（虚劳）；未满十六岁的人称为小儿，患病则称为“疳”（小儿营养不良或慢性消耗性疾病）。这是因为小儿先天禀赋的气血虚弱，真元不足，脏腑娇嫩，容易受到损伤。有的因为在一岁以内，肠胃尚未坚固，乳食混杂摄入，所吸吮的乳汁与所吃的食物不能相互消化融合而形成的；有的因为孩子刚满一岁多，甜食肥腻无节制，积滞日久，导致面色发黄、肌肉消瘦而形成的；有的因为在两三岁之后，恣意食用杂物，食物久留形成积滞，又因消导攻积太过，反而损伤了胃气而形成的；有的因为大病之后，出现呕吐、腹泻、疟疾、痢疾等症状，乳食摄入减少，以致脾胃失去滋养而形成的；有的因为乳母寒热不调，或在喜怒、房事劳累之后，立即给孩子喂奶而形成的。究其病源，无不由于脾胃。因为胃是受纳水谷的海，水谷的精微之气化为营气，剽悍之气化为卫气，营卫充盈，灌溉五脏，所以气足则毛孔致密，腠理坚强，血足则颜色鲜妍，皮肤润泽。如果患疳病的形体不魁梧，这是气不足的表现；患疳病的色泽不华彩，这是血不足的表现。然而这一切都源于脾胃因积滞化热，因热而成疳，消耗气血，煎熬津液。该证初起时，不过表现为尿液像米泔水一样浑浊，午后有潮热；若拖延日久失治，则会转变为头皮光亮紧绷，毛发焦枯稀疏，腮部收缩，鼻干，口馋唇白，两眼昏花溃烂，经常揉眉擦鼻，脊背耸起，身体发黄，磨牙咬指甲，极度口渴且自汗，大便色白泻出酸臭物，腹部胀大且有青筋暴露，特别嗜好瓜果、咸味、炭灰、水泥等异物的，这就是疳病的典型症状。如果说治疗疳病必须攻逐积滞，然而这种积滞是虚中夹实的积滞，恐怕正气无法承受攻伐，从而使疳病更加危险。如果说治疗疳病必须清除热邪，然而这种热邪是虚中夹实的热邪，恐怕清热未尽除，从而使疳病更加危险。如果能够辨别所属证型并妥善治疗，何至于出现厌恶饮食、滑泄不止、乳食直下、牙龈黑烂、头项软弱倒伏、四肢厥冷、下痢肿胀、面色苍白如银、腹部坚硬如石、肌肉呈青黑色、肛门松弛如筒状、口吐黑血、呕吐或排泄蛔虫等种种不治的危重证候呢？因此我不厌其烦地加以解释。
Individuals aged sixteen and above are considered adults; when they fall ill, it is termed Lao (consumptive disease). Individuals under the age of sixteen are considered children; when they fall ill, it is termed Gan (infantile malnutrition or chronic wasting syndrome). This is because their innate Qi and Blood are weak, their True Yuan (Original Qi) is insufficient, their Zang-Fu organs are delicate, and they are prone to injury. Some cases arise within the first year of life when the intestines and stomach are not yet firm; mixed intake of milk and food results in the inability of the sucked milk and ingested food to digest and transform properly. Some cases arise in children just over one year old due to unregulated consumption of sweet and fatty foods, leading to long-standing accumulation, yellowish complexion, and emaciation. Some cases arise after the age of two or three from indiscriminate eating of miscellaneous items, causing food stagnation; excessive use of digestive and purgative methods then damages Stomach Qi. Some cases arise after severe illnesses such as vomiting, diarrhea, malaria, or dysentery, where reduced milk and food intake leads to a lack of nourishment for the Spleen and Stomach. Some cases arise from wet nurses with imbalanced cold and heat, or those who breastfeed immediately after experiencing emotional extremes (anger or joy) or sexual exertion. Ultimately, the source of these diseases lies in the Spleen and Stomach. The Stomach is the sea of water and grain; the essence of water and grain transforms into Ying (Nutritive) Qi, while its vigorous aspect transforms into Wei (Defensive) Qi. When Ying and Wei are abundant, they irrigate the five Zang organs. Thus, sufficient Qi makes pores dense and interstices strong; sufficient Blood gives a fresh complexion and moist skin. If a child suffering from Gan lacks robust physique, it indicates a deficiency of Qi; if their complexion lacks luster, it indicates a deficiency of Blood. All these stem from the Spleen and Stomach: stagnation transforms into heat, heat generates Gan, consuming Qi and Blood and boiling body fluids. Initially, symptoms may only include urine turbid like rice washings and afternoon tidal fever. If left untreated for a long time, it progresses to shiny and tight scalp, scorched and sparse hair, retracted cheeks, dry nose, craving for food but white lips, dim and ulcerated eyes, frequent rubbing of eyebrows and nose, hunched spine, sallow body, grinding teeth, biting nails, extreme thirst with spontaneous sweating, white stools with sour diarrhea, distended abdomen with visible blue veins, and intense cravings for fruits, melons, salty substances, charcoal, cement, or soil. These constitute the typical presentation of Gan. If one claims that treating Gan requires attacking stagnation, this stagnation is "accumulation within deficiency," and aggressive attack may overwhelm the patient's resistance, worsening the condition dangerously. If one claims that treating Gan requires clearing heat, this heat is "heat within deficiency," and incomplete clearing may also worsen the condition dangerously. If one can differentiate the specific patterns and treat them appropriately, how could there be untreatable critical signs such as anorexia, slippery diarrhea, undigested food passing directly through, blackened and rotting gums, flaccidity of the head and neck, cold limbs, dysentery with swelling, silvery-white complexion, hard abdomen like stone, bluish-black muscles, lax anus resembling a tube, vomiting of black blood, or vomiting/passing roundworms? Therefore, I have不厌其烦 (wearyingly) provided this explanation.