Et Tu, B12? Cobalamin Deficiency Masquerading As Pseudo-Thrombotic Microangiopathy

Vitamin B12 deficiency is classically associated with megaloblastic anemia. Possible cobalamin deficiency is not investigated once hemolysis is seen. Around 2.5% of cases can present as pseudo-thrombotic microangiopathy (TMA). A swift identification of this means the difference between an easy solution and a protracted one for the patient. A 74-year-old man with no past medical history presented with exertional dyspnea, fatigue, and increasing anorexia over two weeks. Physical examination including a neurological examination was normal. Laboratory tests revealed pancytopenia, unconjugated hyperbilirubinemia, elevated LDH (lactate dehydrogenase), low haptoglobin, and fragmented red blood cells (RBCs) on the peripheral smear, but normal FDP (fibrinogen degradation product) and fibrinogen. The absolute reticulocyte count was reduced as opposed to the expected elevation. Vitamin B12 levels were undetectable, and severe cobalamin deficiency from pernicious anemia was found to be the paramount etiology. Cobalamin deficiency causing pseudo-TMA baffles most physicians. Advanced pernicious anemia is thought to cause intramedullary hemolysis, resulting in peripheral pancytopenia. The fragile RBCs are easily sheared, producing schistocytosis without platelet microthrombi. In contrast to hemolytic anemias, reticulocyte count is low given the unavailability of B12 for erythropoiesis. Reticulocytopenia is a universal finding in cases of pseudo-TMA. Around 38.8% of cases with pseudo-TMA are misdiagnosed as thrombotic thrombocytopenic purpura and treated with plasma product therapy. Keeping an eye out for reticulocytopenia in cases of hemolysis could mean a world of difference for the patient.

MON-701 Uncontrolled Diabetes Presenting as Isolated Sixth Nerve Palsy

BACKGROUND Our case report demonstrates acute onset of diplopia due to Isolated Sixth Nerve Palsy (ISNP) secondary to uncontrolled T2DM, presenting as an ophthalmoplegia. The most frequent one, is ISNP with an incidence of 11.3/100.000 ¹. Vasculopathic ISNP is associated with atherosclerosis in patients older than 50 years ¹.

CASE PRESENTATION A 63 year-old male with history of T2DM, HTN, HL, came for evaluation of acute onset double vision 3 days prior. He noted diplopia while attempting to park his car; he saw that tracking to the left with his eyes would elicit double vision. Denied recent travel, trauma, headache or dizziness. He was awake and alert, BP 200/110mmHg, BMI 33. No pathologic murmur. He had PERRLA bilaterally but impaired lateral rectus muscle movement on the left side. Otherwise, EOMI on the right side. No facial asymmetry or ptosis. Overall, findings positive for ISNP. BMP only remarkable for a glucose of 297, HA1c was 10.0. Head CT was negative for any acute intracranial abnormality. Orbital MRI did not show acute infarction or masses. Patient was admitted for acute diplopia due to ISNP. Differential diagnoses were neoplasm, migraine, MS and diabetic neuropathy. Based on the aforementioned data, we suggested that T2DM was the probable cause. Counseling on improving glycemic control was given. Unfortunately, patient was lost to follow up. DISCUSSION ISNP remains an elusive entity; atherosclerotic risk factors such as DM, HTN, HL, hyperhomocysteinemia ² or viral infections ³ have been reported in association. This type of palsy seems to be more frequent in children and can be recurrent in nature.

In adults, the most likely cause of ISNP seems to be ischemic mononeuropathy or more aggressive etiologies such as temporal arteritis ⁴. Inconclusive images prove even a higher diagnostic challenge ³. Of note, we found a case demonstrating evidence for Eicosapentaenoic Acid in the improvement of ISNP with recovery in as shortly as 8 weeks. The basis of this treatment lies in the recovery of endothelial function focusing on the anti-platelet and anti-inflammatory effects of the drug^2,4. REFERENCES (1). Elder, Christopher, et al. “Isolated abducens nerve palsy: update on evaluation and diagnosis.” Current neurology and neuroscience reports 16.8 (2016): 69. (2). Takenouchi, Yasuhiro, et al. “Eicosapentaenoic acid ethyl ester improves endothelial dysfunction in type 2 diabetic mice.” Lipids in health and disease 17.1 (2018): 118. (3). Azarmina, Mohsen, and Hossein Azarmina. “The six syndromes of the sixth cranial nerve.” Journal of ophthalmic & vision research 8.2 (2013): 160. (4). Yanai, Hidekatsu, and Mariko Hakoshima. “Eicosapentaenoic Acid for Diabetic Abducens Nerve Palsy.” Journal of Endocrinology and Metabolism 7.4 (2017): 131–132.

Non–invasive sampling of endangered neotropical river otters reveals high levels of dispersion in the Lacantun River System of Chiapas, Mexico

Patterns of genetic dispersion, levels of population genetic structure, and movement of the neotropical river otter (Lontra longicaudis) were investigated by screening eight polymorphic microsatellites from DNA extracted from fecal samples, collected in a hydrologic system of the Lacandon rainforest in Chiapas, Mexico. A total of 34 unique genotypes were detected from our surveys along six different rivers, and the effect of landscape genetic structure was studied. We recovered 16 of the 34 individuals in multiple rivers at multiple times. We found high levels of dispersion and low levels of genetic differentiation among otters from the six surveyed rivers (P > 0.05), except for the pairwise comparison among the Lacantún and José rivers (P < 0.05). We recommend that conservation management plans for the species consider the entire Lacantún River System and its tributaries as a single management unit to ensure the maintenance of current levels of population genetic diversity, because the population analyzed seems to follow a source–sink dynamic mainly determined by the existence of the major river.

Influence of the sex of the transmitting grandparent in congenital myotonic dystrophy

To analyse the influence of the sex of the transmitting grandparents on the occurrence of the congenital form of myotonic dystrophy (CDM), we have studied complete three generation pedigrees of 49 CDM cases, analysing: (1) the sex distribution in the grandparents' generation, and (2) the intergenerational amplification of the CTG repeat, measured in its absolute and relative values, between grandparents and the mothers of CDM patients and between the latter and their CDM children. The mean relative intergenerational increase in the 32 grandparent-mother pairs was significantly greater than in the 56 mother-CDM pairs (Mann-Whitney U test, p < 0.001). The mean expansion of the grandfathers (103 CTG repeats) was also significantly different from that seen in the grandmothers' group (154 CTG repeats) (Mann-Whitney U test, p < 0.01). This excess of non-manifesting males between the CDM grandparents' generation with a smaller CTG length than the grandmothers could suggest that the premutation has to be transmitted by a male to reach the degree of instability responsible for subsequent intergenerational CTG expansions without size constraints characteristic of the CDM range.

Protein digestibility of methionine supplemented common beans (Phaseolus vulgaris) in adult human subjects

The study reports on the protein digestibility of five cultivars of common beans (Phaseolus vulgaris) of different color, tested in young adult human subjects, as the sole dietary protein source. Cheese protein was used as reference protein. The cooked beans provided 0.65 g protein/kg/day, and energy intake was adjusted to 45 kcal/kg/day. Results indicated apparent protein digestibility to vary from 49.6 to 62.1%. White colored beans showed the highest value, while black beans gave the lowest. Cheese protein showed an apparent protein digestibility of 76.2%. The true protein digestibility was calculated using the endogenous nitrogen excretion values obtained in the study, as well as literature values. Digestibility increased as expected, but it is still low as compared to other protein sources. A high correlation was found between dry matter digestibility and protein digestibility. Fecal nitrogen was fractionated between soluble and insoluble nitrogen in a 0.02 N NaOH solution. This assay was also carried out in the cooked beans, and findings revealed that the soluble nitrogen fraction was highly correlated with protein digestibility, with a correlation coefficient of -0.94. This fraction, still to be identified, could very well be responsible for the low digestibility values found for common beans in human subjects.

[Protein digestibility and energy in diets based on rice and beans in human adults]

Four studies were carried out for the purpose of measuring the digestibility of diets based on rice and beans (Phaseolus vulgaris), and in order to quantify the effect of their supplementation with animal protein (milk) and energy (oil), on the energy and protein digestibility of such diets in human adults. Diets were offered so that they supplied 46, 72, and 103 mg N/kg/day. When the basal diet--where rice provided 60% of the protein and beans 40%--was administered at a level of 102.5 mg of nitrogen/kg/day and 49.5 Kcal/kg/day of gross energy, an apparent and true nitrogen, energy and metabolizable energy digestibility of 59.1, 70.8, 93.8 and 92.5%, respectively, were observed. When substituting 10% of the vegetable protein by milk protein in the same diet, the same indicators revealed a digestibility of 65.3, 76.8, 93.5 and 92.1%, respectively. The information indicates that supplementation with animal protein improves nitrogen absorption at any of the energy levels studied. In contrast, caloric supplementation does not have any positive effect on nitrogen or energy absorption. It was also found that nitrogen apparent digestibility increases significantly when the N level in the diet is raised, and stabilizes when intake exceeds 100 mg nitrogen/kg/day. It is therefore proposed that for digestibility studies in diets where animal protein is utilized at a nitrogen level of around 120 mg/kg/day, true digestibility remains constant, no matter what nitrogen level is used in the diet.

Composition and potential use of some tropical fruits

The nutritional role fruits could play in poor-quality diets, as sources of vitamin A and ascorbic acid, is described. Likewise, summarized information is presented on the use of some unknown tropical fruits relatively abundant in Central America as components of high-protein foods, providing nutrients such as provitamin A and ascorbic acid, as well as a variety of flavors. In these studies the fruit pulp as a purée was added either fresh or drum-dried, to a corn-soybean blend. In all cases there occurred a decrease in protein quality, which was more marked for some fruits than for others, probably due to the dehydration process used. The chemical composition of other tropical fruits, not consumed by people but which could be used as animal feed, is also presented. This type of fruits includes the Chalum (Inga, spp.) and some Cucurbitaceae. Others contain seeds with a high oil and protein content. Among the latter, Jícara (Crescentia alata) offers very good industrial possibilities.