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TIPPS: The International Placental Pathology Study Group?

11 Sep

 

Some years ago, I had initiated a group, MAPS,  (MidAmerica Placenta Study group) with the idea that it would encompass placental pathologists who could easily get together to meet. I sent out a newsletter with placental slides for discussion. We had 2 meetings. One locally in which the pathologists came more or less locally, from St. Louis, Detroit, Cleveland, Chicago, and Birmingham Alabama. Kurt Benirschke came from San Diego. The next meeting was in Toronto preceding the SPP meeting and by then we had members from all over as far away as Australia. Given the capability of the internet for rapid communication, I think we should form The International Placental Pathology Study Group, (TIPPS Group).

 

I am going to use a recent paper to provide an example/argument for the value of an online interactive placental/perinatal pathology group (1). The paper reviews the association of a blood clot received with the placenta with finding basal plate myofibers on microscopic examination.  The logic of the study is that if a placenta has focal adherence to the myometrium, it will not separate immediately after postpartum contraction of the uterus. However, a portion will separate, and beneath that separated area of retained placenta there will be decidual hemorrhage. Recent reports that basal plate myofibers are a marker of increased risk for placental accreta in subsequent pregnancies, makes improved criteria for finding the lesion clinically important.

 

As with many papers as I read them I have questions I wish I could ask the authors. I had trouble understanding how the placentas were selected. The N for the study is 156 “routine placentas”. They represented 11% of 1,471 “placenta cases”.  To me this could mean two different things. Either there were 156 placentas submitted to pathology from 1,471 placentas delivered, or 156 placentas were selected for the study presumably because they had been grossed by a specially trained pathology assistant and then evaluated by a board certified pediatric pathologist. There was no review of the clinical charts, and certainly no prospective attempt to obtain information about type of delivery, vaginal bleeding, length of third stage of labor, manual extraction, history of prior Cesarean deliveries, location of the placenta in the uterus. Some information however was provided based on the pathology requisition. Was there enough clinical information to exclude bias in which placentas were sent to pathology? For example, if all Cesarean sections, or manually removed placentas, or postpartum hemorrhage were sent to pathology, then the prevalence of either the evidence of an acute hemorrhage or of myofibers might be enhanced.  I was surprised that 21% of cases had “significant retroplacental blood and that 21cases (13.5%) had basal plate myofibers (some detected by actin). The authors describe clinical criteria as well as histological features, that suggest using an actin stain, but it was less clear how they had selected the individual cases. While I don’t think these questions (misreadings) of the paper would have any impact on the conclusions, would it not be helpful to be able to communicate directly with the authors and  have questions answered or points clarified. The authors likely have more information than they can impart in the confines of a formal paper.

I would also like the ability to have an open discussion of placenta accreta in general.  In my page on Chorioamnionitis, I organized it around naïve questions, and I think that is a good approach for out of the box discussion. For example, I have assumed that placenta accreta forms over an area without decidua and the chorion plate then attaches firmly to the muscle. As a result the placenta cannot be detached from the uterus (as it also can not be detached from the decidual tissue). What do we know about this gluing? I believe that fetal fibronectin and annexins are critical components. But how strong is this gluing? In classic cases of accreta with hysterectomy, the placenta remains adherent in some areas with the cleavage going through the placental tissue. How much force does it take to remove a placenta with cleavage through the myometrial layer without tearing the placenta?

How many patients with BPMF had risk factors that far exceed those of histological risk, such as placenta over an old C-section scar? What is the mechanism of accreta in those who do not have clinical risk factors?  Perhaps a plausible mechanism is that the implantation in some way destroys the underlying endometrium in some cases. How does this relate to the other histological lesions reported in the paper, which did not reach statistically significant correlations? Finally, with mechanical removal of the placenta in cases with accreta, why does the uterus not contract and stop the maternal hemorrhage?

Most important to me was that the article reminded me of the useful studies that could be accomplished if we worked as a large network of perinatal pathologists. A simple study would be to look at prior placentas from cases that had Cesarean hysterectomy specimens with confirmed placenta accreta. Any such study would want to collect some basic data on gravidity, prior Cesarean sections, and the gravid order of any placental pathology found. We would also want to keep track of the number of sections taken of the placental base. This study would be retrospective, with specific criteria for basal plate myofibers. The controls could be 2 placentas based on gestation and proximity to the index case. Slides could be blindly reviewed by other pathologists in the study, and questionable cases could be reviewed by all using digital images. The group could help navigate the administrative side such as IRBs and HIPPA in the USA. We might be able to find some funding for recuts and mailing, and find statistician help. The authors of the above paper might be the ones to initiate and coordinate it, or someone else who is so inspired.

I am just throwing out ideas.  Are there any others out there who think this might be a good idea? I suspect others might have different goals or structures for the group. I hope to hear from you.

(1) Wyand R., Cramer S. F., Oshri A., Heller D. S. Association of Retroplacental Blood with Basal Plate Myofibers. Pediatr Develop Pathol (2018) 21:371-379.

A Simple Measure: Kick counts (and a plea for measuring the untethered length of the umbilical cord)

8 Sep

The following news article on Kick Counts strikes me as very important:

 https://www.huffingtonpost.com/entry/counting-kicks-prevent-stillbirths_us_5b927693e4b013f66bd56b19

The success of a program to educate mothers about kick counts in reducing stillbirth may still need further confirmation in other states, but it is a very promising start.

The obstetricians seem to accept the cord wrapping as the cause of death. No one is still doing another simple measure, the length of cord from the start of the wrapping to the placenta. Our simple in vitro research suggests that too short of a functional free cord length put the cord for risk of torsion that can collapse umbilical vein blood flow. If obstetricians started recording this length we might learn when the shortness of this distance becomes dangerous.

The article also does not state explicitly, but implicitly shows, that there is time to rescue the infant. The innovative studies of Drs Theonia Boyd, Mana Parast and others have shown that there is time for fetal vascular occlusive lesions to develop in the placenta, which is evidence of hours to days of a continuing or intermittent process, before fetal death. The autopsy of stillborn infants often shows pleural and pericardial effusions, and dilated cardiac chambers, suggestive of less than immediate asphyxia. The pathology evidence suggests that some stillbirths can be detected and prevented. This innovative inexpensive program to just educate mothers is perhaps the most encouraging evidence yet. When I was on the FIMR panel in Louisville, mothers were often aware of some decreased fetal movement, but did not know that this was potentially (certainly not always) a symptom of fetal hypoxia and needed prompt evaluation.

Note: I have not reviewed clinical studies of kick count as an intervention. I have one reference showing a lack of effectiveness. (1) There is an area that I would not ordinarily review as a pathologist. Does anyone have a useful review?

(1) Grant A, Elbourne D, Valentin L, Alexander S: Routine formal fetal movement

counting and risks of antepartum late deaths in nomally formed

singletons. Lancet 1989, 2:345-347.

 

 

 

Umbilical cord accident 2

24 Aug

I realized that the umbilical cord page was missing the latter portion of the original book chapter. The wording was not identical with the page already on the web, but the section divides were identical. I copied that second portion to the new page. I can not upload videos with this free version of WordPress.

Just added page on fetal vascular malperfusion

23 Aug

I added a page from the obstetrical pathology textbook I had intended to publish. My goal was to create a book for both obstetricians, and pathology residents/fellows. Many of the pages I have published on this site are from that effort. I have tried to update some, but they would all need further updating and editing; nevertheless I hope they will be useful.

The pages also reflect the basis for the detailed anatomic portion of the protocol for the Stillbirth Project. Even if I never find a position from which I can accomplish that study, the pages will be a source of references and explanations should someone else want to carry it through.

Pathology Manual

19 Aug

I am going to post the material from my lectures on stillborn autopsy technique. The images are not meant for the general public, and I have labeled them Pathology Manual. They lay the foundation for the fuller development of the stillbirth research protocol, and may be useful to residents and fellows in pathology. I could not recover the original images and used the powerpoint images that are of lower resolution than I would have preferred. The plan is replace these over time with better images. I will be posting each topic separately and have already posted Postmortem Retention, and now Gestational Age.

The goal of the Stillbirth Study is to have the best clinical estimate of gestational age, and to compare it with the gestational development external and internal anatomic features of the infant. Gestational age is a foundation for evaluating the cause of death. The study would also investigate any independence of individual organ system development from the overall development.

Stillbirth Research Idea

16 Aug

I have posted the outline/synopsis of a research idea for studying the underlying causes of stillbirth as part of an intense postmortem analysis. As I have argued on this site, I believe intrauterine asphyxia is an important cause of stillbirth even in cases where a specific cause of such asphyxia had not been discovered. I think some hidden causes may be revealed if we could image the umbilical cord in utero prior to delivery of the infant. I have argued how cord wrapping can produce a functionally short cord and in one of my own daughters I have seen the effect of occult cord prolapse. The key advance that makes this study novel is the ability of MRI to identify the anatomic position of the cord in utero. I hope that a study of stillbirth will allow early identification of potentially dangerous cord entanglements and positions that could lead to novel therapies of prevention. I also hope that such information will aid in a better understanding of intrauterine asphyxia in labor and prevent complications and prevent Cesarean sections by again novel approaches to the problem.

Of course the etiologies of stillbirth are more complex and may be a confluence of factors that decrease fetal oxygenation or acid/base balance such as maternal sleep position or sleep apnea, maternal ketosis, various causes of compromised utero-placental circulation, uterine contractors, and unknown factors. This proposal suggests even more detailed postmortem history of the parents, a kind of review of systems, and narrative of events. I also propose detailed analysis of each case with some novel approached to the autopsy and placental examination to be discussed. There are also new blood markers that may be able to aid in identifying conditions such as sleep apnea after the fact. Finally, I propose the review of each case after  the postmortem evaluation is deemed complete by a team with the aim of continuing modification of the study methodology.

This study is an extension of the postmortem examination. Numerous risk factors have been identified for stillbirth, but as an example, obesity is a risk factors, but the direct mechanism of death in an individual infant involves more than just maternal obesity. The goal in each case is to improve our ability to explain the death of the infant to the parents and to ourselves. By looking at each case in detail, not for risk factors, but for a plausible and, as much as possible, provable, sequence of biological mechanisms. The constant review of the cases will accumulate knowledge that cannot be obtained otherwise, and hopefully will set the stage for controlled trials of new approaches. Stay tuned.

If anyone is interested in joining the study please email me, bendonrw@gmail.com.  I have a Powerpoint that explains some more detail. The study is still at an early point in development, and is not funded. However, commitments to the concept by obstetricians, pathologists, radiologists, and nurses will help provide concrete evidence to potential funders that the project is viable.

Open letter to obstetricians

18 Jul

Some of the pages on this blog were from a sequential series of historical chapters on fetal asphyxia starting from Dr. Little and progressing to Dr. Ron Myers key discoveries in free range monkeys, and then to later refinements in ovine models. The final chapter was on the medico-legal implications.

I have summarized this effort in the open letter that I just posted. The scientific basis of this letter is in the other posted pages on the site which review the published literature with references. I would be grateful to pathologists who utilized this site, if they would give this letter to obstetrician colleagues, and hopefully provide me with some feedback.

My email address is bendonrw@gmail.com.

Thanks,

 

Bob Bendon, MD

Postmortem retention etc.

11 Jul

My older blog had my power point lectures on the perinatal autopsy. When I gave those lectures, I had a detailed handout for each slide. I had intended to publish these as an appendix to the book that will never be published. I had not planned to blog these lectures again. However, I had promised a local pathologist who had lent me the use of a microscope to send him the references to the articles by Genest and colleagues that I had found very useful. To accomplish that goal,  I have posted a page on this topic. I hope it is useful to others as well.

Breus Mole etc.

30 May

I have added another page on subchorionic lesions on the placental surface. This was a segment of a chapter I wrote (unpublished) that followed the section on retroplacental hematoma. The previous page on placenta accreta precedes that section. A condensed versions of the RPH section will I hope soon be published in “Pathology of the Placenta: A Practical Guide” editors Khong, Mooney, Nikkels, Morgan and Gordijn.

Placenta Accreta post

20 May

This post was part of the chapter on retroplacental hematoma. I used the portion on RPH for the consensus textbook on placenta to be published. I decided to publish this portion on placenta accreta here. There are some new references to be added, which I may get to later. I feel the portion is still valuable since it reflects my experience.

I have given up trying to find a position. The position in perinatal pathology at Feinberg has been posted three times. I applied the first 2 and was neither interviewed nor my references contacted. Time to stop. However, I am grateful to those of you who do visit the site, and hope it is helpful. I have more to post if anyone finds it useful.