Palva T, Northrop C, Ramsay H
Department of Otolaryngology, University of Helsinki, Finland.
Otol Neurotol. 2001 Jul;22(4):433-43. doi: 10.1097/00129492-200107000-00003.
An influx of amniotic fluid cellular content (AFCC) into the middle ears during birth may lead to the development of a chronic inflammatory process in the form of varying amounts of granulation tissue even if signs of otitis media are absent. This foreign body neonatal otitis media may predispose the child to recurrent otitis media.
Foreign body neonatal otitis media caused by AFCC was described by Aschoff and elaborated by Wittmaack 100 years ago. Recent studies have shown how AFCC spreads to various middle ear compartments and causes histologic changes, the severity of which is related to the amount of AFCC. Specific elements become phagocytized after the first months of life but have caused the formation of inflammatory polyps and granulation tissue with round cell secretions in the meantime.
Ten temporal bones from the Temporal Bone Foundation, derived from infants aged 5 months to 1 year 11 months, were serially sectioned at 20 microm, saved at 0.2-mm intervals, numbered, and stained with hematoxylin and eosin. Every slide was studied for the presence, nature, and stage of pathologic tissue changes of the middle ear and the mastoid antrum.
Pseudocystic granulation tissue was massive in the temporal bone of the 8-month-old child born through thick meconium. Severe changes were present in the temporal bones of two infants aged 5 months, one of which showed traces of AFCC. In the temporal bones of two older children, long-standing changes were minor, one of them still showed traces of AFCC. Fresh acute changes and long-standing histologic changes occurred side by side.
Neonatal otitis media caused by AFCC can give rise to extensive granulation tissue and round cell secretion, which is likely to make the ear susceptible to infectious otitis media. Cumulative development of granulation tissue as a result of infection may lead to blockage of attic aeration and drainage pathways, causing irreversible adhesive otitis media. A data base should be formed of all neonates born through meconium-stained amniotic fluid to allow a comparison with those born through clear fluids. Surgery with the creation of auxiliary aeration pathways becomes advisable in the treatment of ears with massive development of granulation tissue.
出生时羊水细胞成分（AFCC）流入中耳，即使没有中耳炎体征，也可能导致不同数量肉芽组织形式的慢性炎症过程的发展。这种异物性新生儿中耳炎可能使儿童易患复发性中耳炎。
100年前，阿绍夫描述了由AFCC引起的异物性新生儿中耳炎，维特马克对其进行了详细阐述。最近的研究表明AFCC如何扩散到中耳的各个腔室并引起组织学变化，其严重程度与AFCC的数量有关。特定成分在出生后的头几个月被吞噬，但在此期间已导致炎性息肉和伴有圆形细胞分泌物的肉芽组织形成。
从颞骨基金会获取10块颞骨，来自5个月至1岁11个月的婴儿，以20微米的厚度连续切片，每隔0.2毫米保存，编号，并用苏木精和伊红染色。对每张切片进行中耳和乳突气房病理组织变化的存在、性质和阶段的研究。
通过浓稠胎粪出生的8个月大儿童的颞骨中存在大量假囊性肉芽组织。5个月大的两名婴儿的颞骨有严重变化，其中一名显示有AFCC痕迹。在两名年龄较大儿童的颞骨中，长期变化较小，其中一名仍显示有AFCC痕迹。新鲜的急性变化和长期的组织学变化并存。
由AFCC引起的新生儿中耳炎可导致广泛的肉芽组织和圆形细胞分泌，这可能使耳朵易患感染性中耳炎。感染导致的肉芽组织累积发展可能导致上鼓室通气和引流途径受阻，引起不可逆的粘连性中耳炎。应建立所有通过胎粪污染羊水出生的新生儿的数据库，以便与通过清澈羊水出生的新生儿进行比较。对于肉芽组织大量增生的耳朵，手术建立辅助通气途径是可取的治疗方法。
