Opinion ID: 220774
Heading Depth: 4
Heading Rank: 2

Heading: Testimony of Dr. Craig Wong

Text: According to Huerta, Dr. Craig Wong was prepared to testify that, to a reasonable degree of medical certainty, subpotent tacrolimus dispensed by BioScrip caused Huerta’s kidney rejection. The district court, however, found that Dr. Wong’s testimony was unreliable because it was not supported by any direct evidence that the BioScrip tacrolimus suspension was actually subpotent and because Dr. Wong’s testimony was based on the erroneous assumption that Huerta had taken the recalled tacrolimus, which she had not. Aug. 13, 2010 Op. at 11; see Goebel, 346 F.3d at 991. Insofar as Dr. Wong reached his causation opinion by rendering a “differential diagnosis,” the district court also found that Dr. Wong’s methodology fell short. A -8- “differential diagnosis” is one rendered by a physician who first “‘rule[s] in’ all scientifically plausible causes of the plaintiff’s injury. The physician then ‘rules out’ the least plausible causes of injury until the most likely cause remains.” Hollander v. Sandoz Pharm. Corp., 289 F.3d 1193, 1209 (10th Cir. 2002) (quoting Glasteter v. Novartis Pharm., Corp., 252 F.3d 986, 989 (8th Cir. 2001)). Then, “[t]he remaining cause is the expert’s conclusion.” Id. (citing same). Our circuit has recognized that a differential diagnosis can be admissible if the district court concludes that it is reliable and if general causation has been established. Goebel, 346 F.3d 987 (citing Hollander, 89 F.3d at 1210). As the Sixth Circuit has explained, however, Calling something a ‘differential diagnosis’ . . . does not by itself answer the reliability question but prompts three more: (1) Did the expert make an accurate diagnosis of the nature of the disease? (2) Did the expert reliably rule in the possible causes of it? (3) Did the expert reliably rule out the rejected causes? If the court answers “no” to any of these questions, the court must exclude the ultimate conclusion reached. Pluck v. BP Oil Pipeline Co., --- F.3d ----, 2011 WL 1794293, 5 (6th Cir. 2011) (citing Tamraz v. Lincoln Elec. Co., 620 F.3d 665, 674 (6th Cir.2010) (cert. denied, --- S. Ct. ----, 2011 WL 863879 (May 16, 2011) (Nos. 10-1122, 10A744)). To that end, the district court answered “no” to the last two questions. The district court found that Dr. Wong “ruled in” subpotent tacrolimus as a potential cause of Huerta’s kidney rejection because of the severity of Huerta’s rejection and the concurrent tacrolimus recall when she was hospitalized. Although Dr. Wong did -9- not know which manufacturer issued the recall, “he assigned a ‘blanket blame on every liquid [tacrolimus] preparation.’” Aug. 13, 2010 Op. at 6 (quoting R., Vol. I at 72). Because it turned out that Huerta had not taken the recalled tacrolimus, and because there was no direct evidence of the potency of the tacrolimus suspension or of Huerta’s tacrolimus levels when she was admitted to the hospital, the district court found that there was no way to “test” Dr. Wong’s hypothesis that subpotent tacrolimus caused Huerta’s kidney rejection. Id.; see also Daubert, 509 U.S. at 593-94. The district court also found that Dr. Wong’s testimony was based on Huerta’s attorneys’ erroneous representations that test results showed that the tacrolimus suspension was subpotent when such test results did not exist. Aug. 13, 2010 Op. at 6-7. When he was informed that the purported test results did not actually exist, Dr. Wong conceded that “if there [wa]s ‘no evidence to show that [Bioscrip’s tacrolimus suspension] was subpotent, then I don’t think anybody can say what caused the rejection, and that’s just history.’” Id. at 7 (quoting R., Vol. II at 489). The district court also found that Dr. Wong’s “ruling out” Huerta’s noncompliance with her medication regime as a potential cause of her kidney rejection was wanting. It was based only on “knowing” Huerta’s family, without any investigation into whether Huerta’s family had properly administered her medication in the weeks before the rejection and without examining the suspension bottles to determine how much of the suspension had been used. Id. at 11-12. -10- Given these deficiencies, the district court found that Dr. Wong’s opinion was “not ‘supported by appropriate validation – i.e., ‘good grounds,’ based on what is known.’” Id. at 11 (quoting Daubert, 509 U.S. at 590). As a significant matter, we find telling Dr. Wong’s concession that he would only be speculating as to the cause of Huerta’s kidney rejection when it was revealed to him that there was no direct evidence measuring the potency of Huerta’s tacrolimus suspension. Our court has previously stated that “[t]o be reliable under Daubert, an expert’s scientific testimony must be based on scientific knowledge . . . and not mere ‘subjective belief or unsupported speculation.’” Goebel, 346 F.3d at 991 (quoting Daubert, 509 U.S. at 590); see Mitchell v. Gencorp Inc., 165 F.3d 778, 780 (10th Cir. 1999). This indicates that the district court did not abuse its discretion in excluding Dr. Wong’s testimony as unreliable. Moreover, given Dr. Wong’s concession, his final testimony and the evidence and methodology upon which he relied are unclear to us. See Mitchell, 165 F.3d at 781 (“At a minimum, the expert testimony should include a description of the method used to arrive at the level of exposure and scientific data supporting the determination. The expert’s assurance that the methodology and supporting data [are] reliable will not suffice.”) (citing Moore v. Ashland Chem., Inc., 151 F.3d 269, 276 (5th Cir. 1998) (en banc)). Only piecemeal excerpts of Dr. Wong’s deposition testimony are provided to us, and Huerta’s briefing does not articulate his final proffer. On this record, we cannot find that the -11- district court was manifestly unreasonable in excluding Dr. Wong’s testimony as unreliable. None of Huerta’s arguments persuades us otherwise. Huerta argues that Dr. Wong’s testimony was supported by his observation that her kidney rejection was one of the most severe and catastrophic rejection episodes he had seen. The district court, however, held only that Dr. Wong could testify that Huerta’s kidney rejection was severe and catastrophic. What the district court found lacking, however, was the causal link between the severity of the rejection and the potency of BioScrip’s tacrolimus suspension. And we find that the district court was within its discretion to so conclude. See Goebel, 346 F.3d at 992 (“‘A court may conclude that there is simply too great an analytical gap between the data and the opinion proferred.’”) (quoting General Elec. Co. v. Joiner, 522 U.S. 136, 146 (1997)). Our court has stated that “a differential diagnosis is most useful when ‘the party relying on the diagnosis has offered independently reliable evidence that the allegedly dangerous drug or substance had harmful effects.’” Goebel, 346 F.3d at 999 (quoting Hollander, 289 F.3d at 1210). Here, the evidence appears to be weak or entirely missing to show that the tacrolimus suspension administered to Huerta was subpotent. See, e.g., Nelson v. Tenn. Gas Pipeline Co., 243 F.3d 244, 253 (6th Cir. 2001) (“Without any factual basis from which a jury could infer that the plaintiffs were in fact exposed to PCBs from Station 79, the reasoning and methodology underlying the testimony is not scientifically valid.”). Huerta’s argument that her other experts’ differential diagnoses -12- constituted “direct evidence,” even though they had been excluded as unreliable, is clearly unpersuasive. Aplt’s Br. 17-18. Huerta next argues that contrary to the district court’s findings, Dr. Wong properly ruled out non-compliance with the prescribed treatment as a possible cause of Huerta’s kidney rejection. The district court found that Dr. Wong summarily ruled out noncompliance based only on “knowing” Huerta’s family. Dr. Wong did so even though he acknowledged that Huerta’s physicians were concerned that non-adherence may have led to her subsequent kidney rejection episode in May of 2007 when she was taking a different form of tacrolimus. Aug. 13, 2010 Op. at n.6. Huerta argues that Dr. Wong properly based his “ruling out” of non-adherence on his seeing non-adherence in patients “on a quite regular basis.” Aplt’s Br. 16 (quoting R., Vol. I at 112). Dr. Wong also testified that non-adherence would not have caused the type of rejection he saw in Huerta. Id. (citing same). Dr. Wong also testified that some teenagers fail to take their medicine “10 to 25 percent of the time and they still kind of manage to do okay.” Id. (citing R., Vol. I at 120). Despite Huerta’s arguments, we cannot conjecture about the viability of Dr. Wong’s conclusion in view of his concession that he would be speculating as to the cause of Huerta’s kidney rejection in the absence of evidence. On the record submitted to us, we are unpersuaded that the district court was unreasonable in finding that Dr. Wong did not properly rule out non-adherence as a potential cause of Huerta’s kidney rejection. Huerta next argues that the district court abused its discretion by faulting her for not providing direct evidence of the potency of the tacrolimus suspension when -13- insufficient tacrolimus remained for testing. To the contrary, the district court did not require direct evidence as a baseline to sustain Dr. Wong’s testimony, but found that in this case, no other evidentiary link could reliably connect the tacrolimus suspension with Huerta’s rejection. Aug. 13, 2010 Op. at 6-7; see also Kumho Tire, 526 U.S. at 153 (“[W]hether Daubert's specific factors are, or are not, reasonable measures of reliability in a particular case is a matter that the law grants the trial judge broad latitude to determine.”) (quoting Joiner, 522 U.S. at 143). By conceding that he could not say what caused Huerta’s kidney rejection without evidence that the tacrolimus was subpotent, Dr. Wong appears to agree with the district court’s assessment. R., Vol. II at 489. Lastly, Huerta argues that the district court mischaracterized Dr. Wong’s testimony as “ruling in” subpotent tacrolimus solely on the assumption that Huerta was administered the recalled tacrolimus. However, Huerta’s argument fails for two reasons. First, the district court recognized that Dr. Wong’s testimony was based on both the severity of Huerta’s rejection and also on the recall. Aug. 13, 2010 Op. at 6. As discussed above, the district court found that while Dr. Wong could testify to the severity of Huerta’s rejection, that testimony fell short of establishing subpotent tacrolimus as a cause for Huerta’s kidney rejection. Second, as to the recall, Dr. Wong testified that at the time of Huerta’s 2006 hospitalization, he hypothesized that subpotent tacrolimus could have caused Huerta’s kidney rejection by assigning a “blanket blame on every liquid [tacrolimus] preparation and, you know, guilty unless proven innocent.” Id. (quoting R., Vol. I at 72). Whether Dr. Wong continued to rely on this in his final testimony given his -14- prior concession is unclear to us from the record, and on this we also decline to speculate. Accordingly, this last argument clearly fails. For all the foregoing reasons, we find that the district court did not abuse its discretion in excluding Dr. Wong’s testimony.