ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 Methods: We evaluated 99 cases (94 tissue microarrays) of decid- ual tissue (72 eutopic; 27 ectopic). WT1 nuclear immunoexpression was independently evaluated by four pathologists. Percentage and intensity of positive cells were estimated using a semi-automated open-source software. A staining score was obtained by multiply- ing the percentage and intensity of positive cells. Clinical data was reviewed and the results were statistically analysed. Results: We evaluated 99 cases of decidual tissue in total, 36,4% associated with pregnancy (23 eutopic; 13 ectopic) and 63,6% non-pregnancy associated (49 eutopic; 14 ectopic). Nuclear expression of WT1 was observed in 93,9% cases (97,2% in preg- nant women; 92,1% in non-pregnant women), with no statistical differences (p=0,550). The percentage and nuclear intensity of cells were higher in non-pregnancy related decidua, mainly in eutopic location (p<0,001 and p=0,003, respectively). Accord- ingly, the WT1 score was also higher in non-pregnancy related eutopic decidua [moderate (14,3%); strong (77,6%); p=0.034]. The WT1 percentage of positive decidual cells was associated, independently of the pregnancy status, with the eutopic location (p=0,024). Conclusion: In our study of a case series we did not verify a higher imunoexpression of WT1 associated with pregnancy status. We verify a higher percentage of WT1-positive decidual cells in eutopic tissues, especially in non-pregnancy related cases. OFP-08-003 Chronic histiocytic intervillositis and related clinical findings: a multicentric, retrospective analyses of 34 cases in a 17 year period M. de Brito Pereira*, S. Carralas Antunes, E. Vitorino, R. Ilgenfritz, J. Tavares *Pathology Department, Hospital CUF Descobertas, Lisbon, Portugal Background & objectives: Chronic histiocytic intervillositis (CHI) of unknown aetiology is a rare placental disorder defined by the presence of an histiocytic infiltrate in the intervillous compart- ment. According to literature, it is related to poor foetal outcome, maternal autoimmune diseases (AD) and recurrence. Methods: A retrospective review was conducted in all placentas and products of conception (over 21000 specimens) received in three major hospitals in Lisbon metropolitan area, between June 2003 and February 2022, to detect cases with CHI as a major finding; cases with other major placental findings were excluded. Medical records were analysed regarding the associated clinical and obstetric data. Results: A total of 34 cases were selected, which corresponded to 32 women with mean age of 37 years (+/- 5 years). Half (17 cases) of pregnancies resulted in viable births, 9% (3 cases) in intrauterine deaths and 41% (14 cases) in spontaneous abortions. In 41% of cases there was intrauterine growth restriction, 3 cases (9%) had a single umbilical artery and 5 (15%) were associated with foetal malformations. Only 25 women had an available medical record, AD were present in 3 (1 a previous diagnosis, 2 revealed after placental evaluation). Recorded recurrency was seen in 2 women and 3 other had a his- tory of repeated aborditions without known histologic assessment. Conclusion: Our incidence of CHI is similar to the literature; regarding the prevalence of maternal AD, our study reveals a lower incidence than usually observed. The question remains if an undiagnosed AD is present at the time of gestation or if CHI can precede the full setting of an AD and, if so, how long it takes between both events. We propose follow-up of these patients in a 5 years period, with special focus on CHI recurrency and AD incidence/prevalence. OFP-08-004 Left ventricular non-compaction in foetal autopsy: a report of 6 cases A. Nadal*, C. Fuster, N. Masoller, Ò. Rosiñol, J. Camacho, O. Gómez *Hospital Clínic, Spain Background & objectives: Left ventricular non-compaction (LVNC) results from arrest of normal process of ventricular com- paction, resulting in a ratio between non-compacted and compacted myocardial layers >1. It is a rare condition of uncertain aetiology although likely genetic with dominant pattern of inheritance. Methods: Cases with LVNC were retrieved from pathology files. Ultrasonographic and genetic data when available were retrieved from clinical charts. Histology when available was reviewed. Results: LVNC was identified in 6 cases (three termination of pregnancies and three intrauterine foetal deaths) out of 3000 foetal autopsies. Gestational ages ranged from 13 to 25 weeks. Four out of five cases had ultrasound abnormalities with two foetal hydrops and one additional subcutaneous oedema. Cardiac abnormalities were identified in two cases. Three out of four cases with available genetic analysis had genetic alterations: X monosomy, 8q23 dele- tion and heterozygous compound LDB3 mutations. Healthy carriers of LDB3 mutations were identified among the relatives of this case. Two of three sibs that shared the heterozygous compound LDB3 mutations had LVNC, one being a live-born girl. Conclusion: LVNC incidence was higher in this foetal autopsy series than it is reported in the paediatric population. Noncompacted cardiomyopathy must be considered in the differential diagnosis in cases of foetal hydrops and dilated cardiomyopathy. It must also be ruled out when other structural cardiac defects are found. The inheritance pattern found in LDB3 mutations, consistent with a recessive pattern, was not previously described. OFP-08-005 Umbilical cord compromise versus other clinical conditions predisposing to placental foetal vascular malperfusion J. Stanek* *Cincinnati Children’s Hospital, USA Background & objectives: Foetal vascular malperfusion (FVM) can be due to cord compromise, hypercoagulability, foetal cardiac dysfunction, or hypoxia. Although the cord compromise is most common, the relative importance of other factors is unclear which is the aim or this retrospective analysis. Methods: 580 placentas were examined: Group 1: 52 placentas with clinical cord compromise/anatomical abnormalities, Group 2: 204 placentas with maternal/ foetal conditions predisposing to FVM; Group 3: 286 placentas with coexisting at least one variable of Group 1 and one variable of Group 2 predisposing to FVM, Group 4: 38 placentas with no clinical conditions or cord factors predisposing to FVM. Results: Average gestational age was the shortest in Group 4, fol- lowed by Groups 1, 2 and 3. Groups 1 and 4 featured more cases with poor prenatal care, less frequent cesarean sections, more fre- quent macerated stillbirths, less frequent neonatal stay in intensive care unit, atherosis of spiral arterioles, retroplacental hematomas, and luminal vascular abnormalities of chorionic villi. Clusters of sclerotic/stromal vascular karyorrhectic/mineralized chorionic villi, large vessel foetal vascular malperfusion, and low grade distal foetal vascular malperfusion were statistically significantly more common in Groups 1 and 3. There were no statistically significant differences in inflammatory and hypoxic lesions or patterns (acute or chronic) or lesions of shallow placental implantation among the groups. S32