Chronic kidney disease of nontraditional causes in central Panama.

BACKGROUND: Over the last three decades, the mesoamerican region has seen an increase in the frequency of patients diagnosed with Chronic Kidney Disease of nontraditional causes (CKDnt) also known as Meso-American Nephropathy (MeN). A region with an increased frequency of patients with Chronic Kidney Disease (CKD) has been identified in central Panama. The present study aims to characterize the clinical presentation of patients with CKDnt in an understudied population of the central region of Panama and to compare them with patients with traditional chronic kidney disease (CKDt). METHODS: A retrospective descriptive study was conducted in a nephrology reference hospital in the central provinces of Herrera and Los Santos, comparing a group of 15 patients with CKDnt to 91 patients with CKDt. Sociodemographic variables, personal history, laboratory parameters, and of renal ultrasound were compared. RESULTS: Patients with CKDnt had a median age of 58 years (IQR: 52-61), significantly lower (P < 0.001) than patients with CKDt with a median age of 71 years (IQR: 64-78). Patients with CKDnt had a history of being agricultural (60%) and transportation (20%) workers, significantly higher than patients with CKDt (15%, P < 0.001 and 0%, P < 0.01 respectively). Renal atrophy and hyperuricemia are significant clinical markers of CKDnt (P < 0.001 and P < 0.05 respectively). CONCLUSION: To our knowledge, this is the first study in Panama to investigate the clinical presentation of patients with CKDnt and one of the few in Central America and the world that compares them with patients with CKDt. In central Panama the typical CKDnt patient is a male in his 50 s who is primarily engaged in agriculture or as a public transport driver. Renal atrophy and hyperuricemia are significant clinical markers of CKDnt. Further studies are needed to help understand the common determinants and risk factors for CKDnt development in Panama and Mesoamerica.

Strategy or symptom: Semantic clustering and risk of Alzheimer's disease-related impairment.

Alzheimer's disease (AD) is the most common form of dementia, impacting global cognitive performance, including episodic memory. Semantic clustering is a learning strategy involving grouping words of similar meaning and can improve episodic memory performance, e.g., list learning. As the APOE ε4 allele is the most validated genetic risk factor for AD, we predicted that its presence would be associated with poorer list learning performance, and we hypothesized that semantic clustering moderates or mediates this association. The sample comprised 699 healthy older adults participating in the CHARIOT PRO Main Study, 169 of whom were APOE ε4 carriers. Participants' ability to form groups of related stimuli (assessed via a categorization task, CAT), and their use of semantic clustering during list learning, were investigated using the Neuropsychological Assessment Battery (NAB). CAT scores predicted the use of semantic clustering in, and performance on, the list learning task. CAT scores were not significantly lower in APOE ε4 carriers, suggesting that the ability to categorize was preserved. However, APOE ε4 carriers made less use of semantic clustering in list learning. Semantic clustering use partially mediated the relationship between CAT scores and list learning performance, and, in women only, moderated the impact of APOE ε4 on list learning performance. The results suggest that better categorization ability is associated with greater use of mnemonic strategies and better performance on memory tasks regardless of genetic risk, but that APOE ε4 carriers make less use of such strategies. Furthermore, female APOE ε4 carriers may benefit more than their non-carriers from using semantic clustering to aid list learning. Thus, semantic clustering may be a contributing factor of their "cognitive reserve", compensating for potential deficits in episodic memory.

The clinical utility of the Warrington Recognition Memory Test in people with a low IQ.

The sensitivity of the Warrington Recognition Memory for Faces (RMF) to reliably localize temporal lobe dysfunction in surgical epilepsy candidates is not as strong as that of the Recognition Memory for Words (RMW). Previous research has indicated that its diagnostic utility is improved in patients with lower IQs. Data from 114 patients with unilateral hippocampal sclerosis was retrospectively examined to explore the accuracy of both subtests in patients with IQs within the low average/borderline impaired and intellectual disability ranges. In our group, the RMF did not discriminate between right and left hippocampal sclerosis, whilst the RMW did. However, many patients functioning within the intellectual disability range are unable to complete the RMW. There is a need to develop neuropsychological protocols appropriate for this group.

The impact of levetiracetam on challenging behavior.

An observational longitudinal design was employed to evaluate whether treatment with the antiepileptic drug levetiracetam (LEV) adversely impacts behavior in people with intellectual disabilities and/or acquired brain damage. Thirty-five adults were assessed once off the drug and once when on LEV therapy, with a 2-month interval between assessments. Behaviors were rated using an adaptation of the Yale-Brown Obsessive Compulsive Scale and the Challenging Behaviour Scale. Challenging behaviors were rated as more frequent and severe when individuals were taking LEV. Behavioral worsening was not related to better seizure control or increased levels of engagement in activities. Families and professionals need to be aware of the potential reversible adverse effects of this drug.