No abstract

Aortitis primarily affected women. Patients with isolated aortitis and giant cell arteritis were generally older than 50 years and, by definition, those with Takayasu arteritis were younger. In patients with isolated aortitis, outcomes were generally good, despite the absence of anti-inflammatory therapy. Accordingly, a conservative approach may be warranted for managing this subset of patients with aortitis.

Methylenetetrahydrofolate reductase (MTHFR) mutations are commonly associated with hyperhomocysteinemia, and, through their defects in homocysteine metabolism, they have been implicated as risk factors for neural tube defects and unexplained, recurrent embryo losses in early pregnancy. Folate sufficiency is thought to play an integral role in the phenotypic expression of MTHFR mutations. Samples of neonatal cord blood (n=119) and fetal tissue (n=161) were analyzed for MTHFR C677T and A1298C mutations to determine whether certain MTHFR genotype combinations were associated with decreased in utero viability. Mutation analysis revealed that all possible MTHFR genotype combinations were represented in the fetal group, demonstrating that 677T and 1298C alleles could occur in both cis and trans configurations. Combined 677CT/1298CC and 677TT/1298CC genotypes, which contain three and four mutant alleles, respectively, were not observed in the neonatal group (P=.0402). This suggests decreased viability among fetuses carrying these mutations and a possible selection disadvantage among fetuses with increased numbers of mutant MTHFR alleles. This is the first report that describes the existence of human MTHFR 677CT/1298CC and 677TT/1298CC genotypes and demonstrates their potential role in compromised fetal viability.

Identification of fungi in tissue sections can be difficult. In particular, species of Aspergillus, Fusarium, and Pseudallescheria all appear as septate, branched hyphae. However, their differentiation can have significant clinical implications, as the latter two groups are often resistant to commonly used antifungal agents. In situ hybridization may assist in rapidly distinguishing these organisms in the absence of available culture. Oligonucleotide DNA probes were directed against the 5S, 18S, or 28S rRNA sequences of three groups of fungi with a high degree of specificity for each. Probes were tested on 26 formalin-fixed, paraffin-embedded tissue specimens, each with culture-proven involvement by one of these organisms: Fusarium species, n = 12; Pseudallescheria boydii, n = 5; Aspergillus species, n = 9 ( probe set validated in an earlier study). Accuracy of both ISH and morphology was compared with culture. Morphologic examination (GMS and PAS) showed a greater sensitivity in detecting fungi (100%) as compared with in situ hybridization (84.6%). When detected, however, DNA probes allowed definitive identification of organisms. While there was no ability to distinguish between the three groups of organisms by morphologic features, ISH probes showed 100% positive predictive value (PPV, 19/19 organisms identified correctly). No cross-reactivity was observed when the probes were tested against other genera (100% specificity). Furthermore, the use of ISH allowed the detection of mixed fungal infections involving multiple organism types in two cases, demonstrating another advantage over morphology. In situ hybridization, directed against rRNA sequences, provides a rapid and accurate technique for distinguishing commonly encountered, nonpigmented filamentous fungi in histologic sections. While less sensitive than morphology, ISH is highly accurate and may help to distinguish between organisms that have similar or identical morphologic features by light microscopy.

Background: Spurious increases in serum troponins, especially troponin T, have been reported in patients with and without acute myocardial syndromes. Methods: We studied 78 autopsied patients without clinical myocardial infarction (MI) and correlated histologic cardiac findings with antemortem serum creatine kinase (CK), its MB isoenzyme (CK-MB), cardiac troponin I (cTnI), and cardiac troponin T (cTnT). Results: There was no significant myocardial pathology in 15 patients. Cardiac pathologies were in five groups: scarring from previous MI or patchy ventricular fibrosis (n = 9), recent MI (n = 27), healing MI (n = 7), degenerative myocyte changes consistent with congestive heart failure (CHF; n = 12), and other cardiac pathologies (n = 8). The median concentrations in the five groups were not significantly different for either CK or CK-MB. Compared with the no-pathology group, only the MI group was significantly different for cTnI, and the MI and other pathology groups were significantly different for cTnT. For patients with MI, 22%, 19%, 48%, and 65% had increased CK, CK-MB, cTnI, and cTnT, respectively; for CHF and other cardiac pathologies combined, the percentages were 28%, 17%, 22%, and 50%. For patients with increased cTnI, 72% and 28% had MI and other myocardial pathologies, respectively; patients with increased cTnT had 64% and 36%, respectively. Patients without myocardial pathology had no increases in CK-MB, cTnI, or cTnT. Conclusions: All patients with increased serum CK-MB, cTnI, and cTnT had significant cardiac histologic changes. The second-generation cTnT assay appears to be a more sensitive indicator of MI and other myocardial pathologies than the cTnI assay used in this study.