Analgesic abuse and kidney disease

Pharmaceuticals imports in Tanzania: Overview of private sector market size, share, growth and projected trends to 2021

BACKGROUND

To assess the extent to which foreign pharmaceutical imports vary from year to year and identifying leading generic and branded formulations, key countries and key importers of pharmaceuticals in private sector supply chain.

METHODOLOGY

A systematic analysis of data for pharmaceutical imports from the Ministry of Health.Data from 2013 to 2016 fiscal years and relevant documents were accessed from the Tanzania Food and Drugs Authority (TFDA). Data cleaning was carried out to remove duplicate entries and to exclude pharmaceutical imports for individual uses, promotion purpose, donations, raw material, medical devices, government institutions and veterinary products.

RESULTS

A total of 397 different suppliers imported pharmaceutical in Tanzania mainland from 2013 to 2016 fiscal years. In the 2013-2014 fiscal year, the private sector suppliers imported pharmaceutical worth 216 U.S million dollars. India ranked as the first country for exporting highest value of pharmaceutical into the country. It displays a 54% cumulative market share of total imports from 2013-2016, followed by Egypt (11.7%), Switzerland and the USA hold 4.1% of cumulative market share. By 2020-2021 fiscal years, we forecast for imported pharmaceuticals to reach a total value of 906 U.S million dollars for the private sector supply chain. All analysis in this study and the forecasted figures are limited to private sector pharmaceutical supply chain only and does not include data for government pharmaceutical supply chain.

CONCLUSIONS

Our result shows that the vast majority of pharmaceutical imports in the private sector supply chain are dominated by imports from India. India is competing with other countries such as Egypt, Switzerland, USA and South Africa among the top importing countries. There was almost an equal distribution of pharmaceutical for both communicable and non-communicable diseases. Data presented shows a growing trend for the market segment for medicines required for the management of non-communicable diseases. Generally, the private sector pharmaceutical market is keeping on rising at a rapid pace. By the year 2021, the growth is forecasted to increase by 28% compared to the current market value. The projected growth rate could be good news for foreign pharmaceutical companies seeking new sources of growth in international pharmaceutical trading. It is also good news to the poor patients if the availability of drugs previously unavailable in the country is significantly increased.

Common Analgesic Agents and Their Roles in Analgesic Nephropathy: A Commentary on the Evidence

An association between non-opioid analgesic agents and chronic kidney disease has long been suspected. The presumed development of chronic renal impairment following protracted and excessive use of non-opioid analgesia is known as analgesic nephropathy. Many clinicians accept analgesic nephropathy as a real entity despite the paucity of scientific evidence. This narrative review aims to summarize the literature in the field. The weight of available observational literature suggests that long-term ingestion of paracetamol and combination mixtures of aspirin and paracetamol are likely to contribute to chronic renal impairment. However, there is no convincing data to implicate non-steroidal anti-inflammatory drugs or aspirin monotherapy in the development of analgesic nephropathy. In the absence of high-level evidence, while controversy persists, it may be prudent for physicians to consider all non-narcotic analgesics to be nephrotoxic with long-term use.

The Alzheimer pandemic: is paracetamol to blame?

HISTORICAL BACKGROUND

The clinical recognition of a form of dementia closely resembling Alzheimer's disease dates from around 1800. The role of analgesics derived from coal-tar in the spread of the pandemic is traced in terms of the introduction of phenacetin (PN) in 1887; its nephrotoxicity; the observation of lesions characteristic of the disease by Fischer and Alzheimer; the discovery of paracetamol (PA) as the major metabolite of PN; the linking of kidney injury and dementia with high PN usage; and the failure of PN replacement by PA to halt and reverse the exponential, inexorable rise in the incidence of Alzheimer-type dementia. Fischer observed his first case before Alzheimer; it is proposed to rename the syndrome Fischer-Alzheimer disease (F-AD). Disease development: PA-metabolising enzymes are localised in the synaptic areas of the frontal cortex and hippocampus, where F-AD lesions arise. The initiating chemical lesions in liver poisoning comprise covalent binding of a highly reactive product of PA metabolism to proteins; similar events are believed to occur in brain, where alterations in the antigenic profiles of cerebral proteins activate the microglia. β-Amyloid forms, and, like PA itself, induces nitric oxide synthase. Peroxynitrite modifies cerebral proteins by nitrating tyrosine residues, further challenging the microglia and exacerbating the amyloid cascade. Spontaneous reinnervation, N-acetyl cysteine administration and tyrosine supplementation may attenuate the early stages of F-AD development.

CONCLUSION

F-AD is primarily a man-made condition with PA as its principal risk factor.

Renal papillary necrosis

Renal papillary necrosis (RPN) is a significant problem in human beings, especially in England and in Australia where it has been reported to account for 15% to 20% of patients needing renal transplants. Many compounds, including aspirin, phenacetin, phenylbutazone, indomethacin, mefenamic acid, flufenamic acid, fenoprofin, naproxen, and ibuprofen have been linked to renal papillary necrosis in human beings. Although the exact mechanism of RPN is unknown, there are several theories that have good scientific evidence behind them. Study of RPN in animals as models for the disease in human beings is limited by several factors, including anatomical differences between human beings and most animal species as well as technical difficulties in studying the renal papilla.

Chemically induced renal papillary necrosis and upper urothelial carcinoma. Part 1

In the past, renal papillary necrosis (RPN) has been commonly associated with long-term abusive analgesic intake, but over recent years a wide variety of industrially and therapeutically used chemicals have been shown to induce this lesion experimentally or in man. Destruction of the renal papilla may result in: (1) secondary degenerative cortical changes which precede chronic renal failure or (2) a rapidly metastasizing upper urothelial carcinoma, which has a very poor prognosis. This article will briefly review the published data on the morphology, function, and biochemistry of the normal renal medulla and the pathology associated with RPN, together with the secondary changes which give rise to cortical degeneration or epithelial carcinoma. It will then examine in detail those chemicals which have been reported to cause RPN in an attempt to delineate structure-activity relationships. Finally, the many different theories that have been proposed to explain the pathophysiology of RPN will be examined and an hypothesis will be put forward to explain the primary pathogenesis of the lesion and its secondary consequences.

Chemically induced renal papillary necrosis and upper urothelial carcinoma. Part 2

In the past, renal papillary necrosis (RPN) has been commonly associated with long-term abusive analgesic intake, but over recent years a wide variety of industrially and therapeutically used chemicals have been shown to induce this lesion experimentally or in man. Destruction of the renal papilla may result in: (1) secondary degenerative cortical changes which precede chronic renal failure or (2) a rapidly metastasizing upper urothelial carcinoma, which has a very poor prognosis. This article will briefly review the published data on the morphology, function, and biochemistry of the normal renal medulla and the pathology associated with RPN, together with the secondary changes which give rise to cortical degeneration or epithelial carcinoma. It will then examine in detail those chemicals which have been reported to cause RPN in an attempt to delineate structure-activity relationships. Finally, the many different theories that have been proposed to explain the pathophysiology of RPN will be examined and an hypothesis will be put forward to explain the primary pathogenesis of the lesion and its secondary consequences.

Inhibition of DNA synthesis and alteration to DNA structure by the phenacetin analog p-aminophenol

p-Aminophenol a structural analog and minor metabolite of phenacetin has previously been shown to be a potent nephrotoxic agent. In this report we have shown that p-aminophenol has a marked effect on DNA function and structure. DNA synthesis was inhibited in a dose-dependent manner in human lymphoblastoid cells after exposure to p-aminophenol. Results suggest that DNA synthesis is inhibited by the action of p-aminophenol on DNA structure. At low concentrations of p-aminophenol a reduction in the degree of supercoiling of cellular DNA is observed, as determined by sedimentation under neutral conditions. However at higher concentrations an increase in sedimentation of nucleoids (supercoiled molecules) is obtained which is indicative of an increased level of supercoiling or a more compact structural form of DNA due to folding or aggregation. The number of single strand breaks in DNA, when determined by sedimentation in alkaline sucrose gradients, increases with increasing dose of p-aminophenol. The increase in strand breakage observed at lower concentrations of p-aminophenol agrees with the reduced sedimentation rate obtained under neutral conditions. At higher concentrations of p-aminophenol the extent of breakage of DNA increases under alkaline conditions but an increase in sedimentation occurs under neutral conditions.

Unsuspected analgesic nephropathy in transitional cell carcinoma of the upper tract: a morphological study

Analgesic nephropathy is known to have a high incidence in Australia where, following the experience in Scandinavia, reports have been published for some time recording the association between analgesic nephropathy and urothelial malignancies. The morbid anatomical features of analgesic nephropathy are now sufficiently well accepted to allow a retrospective study of unselected nephrectomies for transitional cell carcinoma of the renal pelvis and ureter, in order to assess the incidence of analgesic-type changes in this well defined group of malignancies. The records of a large general histopathology department between 1972-1978 were searched and 24 consecutive transitional cell carcinomas in these sites treated by nephrectomy were selected for study. Of these, 21 were suitable for assessment and on review were shown to comprise II cases with papillary changes acceptable as analgesic in type and five which were suggestive of early analgesic change. Of these 16, seven were female, only two were known analgesic abusers and five were recorded as consuming analgesics on a regular basis. These findings suggest that analgesics may play a significant role in the pathogenesis of urothelial malignancy in the general population.

[Toxic nephropathies (author's transl)]

Direct tubular damage, hypersensitivity reaction, metabolically mediated kidney disturbances, and chronic nephropathies are important sequelae of several drugs or their metabolites. In this review the drug-induced kidney disease is discussed from a clinical, histological, and pathogenetic point of view. The knowledge of possible nephrotoxic reactions and their underlying toxins are essential for prevention of this kidney disease.

Carcinoma of the renal pelvis following the abuse of phenacetin-containing analgesic drugs

Five cases of renal pelvic carcinoma are reported in female patients who abused phenacetin-containing analgesics. The mechanism of carcinogenesis in analgesic abuse is discussed and epidemiological factors are considered. The possibility of development of a renal pelvic tumour in patients with analgesic nephropathy is emphasised.

Aspirin, phenacetin, and the kidney: a rheumatism clinic study

In a rheumatism clinic study in Brisbane, the consumption of aspirin and phenacetin compounds (APC) containing more than one kilogram of aspirin and phenacetin was significantly associated with overt renal papillary necrosis (RPN) and with a renal score, but when more than one kilogram of aspirin was taken without phenacetin there was no such association. Analysis and comparison with the parallel New Zealand study showed an overall risk of RPN of at least 10-6% when more than one kilogram of aspirin was taken in APC form, and 0-3% when aspirin was taken without phenacetin. An additive interaction of phenacetin and aspirin is postulated. It is concluded that phenacetin use should be severely restricted.

Phenacetin and analgesic nephropathy

A prospective survey of 322 autopsies of adults conducted some months after phenacetin was removed from a popular compound analgesic showed to reduction in the incidence of advanced or earlier forms of analgesic nephropathy from levels noted in an earlier survey. Apparently active nephropathy was seen in persons taking two different compound analgesics, neither now containing phenacetin. Crystals observed in early and intermediate analgesic nephropathy had no diagnostic significance and represented a tissue breakdown product.