Encephalopathy after Bladder Irrigation with Alum: Case Report and Literature Review

Dose-response relationships in aluminium toxicity in humans

INTRODUCTION

Aluminium exposure is associated with bone disease (an elevated bone content of aluminium and reduced bone formation on bone biopsy) and neurotoxicity (features of altered brain functions and/or typical spike and slow wave waveforms on electroencephalogram) in patients with elevated blood aluminium concentrations.

OBJECTIVES

To critically analyse the literature to determine the dose-toxicity relationships between aluminium exposure and related bone disease and aluminium neurotoxicity.

METHODS

A systematic review of the literature with collation and analysis of individual data of human cases of aluminium exposure was conducted between 1 January 1966 and 30 December 2020. Embase, MEDLINE (OVID MEDLINE), PubMed and TOXNET were searched with the following strategies: "Aluminium AND toxicity OR aluminium AND poisoning OR aluminium AND dialysis OR aluminium AND chronic renal failure OR aluminium AND intravenous" limited to "(human)". Inclusion criteria required individual data relating to aluminium exposure in humans. Papers in which features of aluminium toxicity and analytical confirmation of aluminium exposure could not be determined in individual patients were excluded.

RESULTS

Thirty-seven papers were identified, which included data on 179 individuals exposed to aluminium. The sources of aluminium exposure (median duration of exposure) were: dialysis fluid (48 months) in 110 cases; oral aluminium hydroxide (20 months) in 20 cases; plasma exchange (2 months) in 16 cases; infant formula feed (minimal duration of 2 weeks) in 14 cases; intravesical exposures (2 days) in 13 oncology patients and potable water exposure in six cases.

EXPOSURE TO DIALYSIS FLUID

Of the 110 patients exposed to dialysis fluid, 99 were adults and 11 children, who were analysed separated. Of the adults, 50 with aluminium neurotoxicity had a median aluminium concentration of 467 µg/L (IQR 230 - 752), 28 with aluminium bone disease had a median aluminium concentration of 142 µg/L (IQR 46-309) and 21 with asymptomatic aluminium overload had a median aluminium concentration of 35 µg/L (IQR 26-51). Median aluminium concentrations were significantly greater in patients with aluminium neurotoxicity compared to those with aluminium bone disease (p < 0.0001) or asymptomatic aluminium overload (p < 0.0001).

ORAL ALUMINIUM HYDROXIDE

Of the 20 cases, 11 were adults and nine were children. Of the 11 adults, eight with aluminium neurotoxicity had a median aluminium concentration of 682 µg/L (IQR 438-770) and three with aluminium bone disease had a median aluminium concentration of 100 µg/L (IQR 62-138) (p = 0.007). Of the nine children, five had aluminium neurotoxicity with a median aluminium concentration of 335 µg/L (IQR 229-601), one had aluminium bone disease and an aluminium concentration of 1030 µg/L and three had asymptomatic aluminium overload with a median aluminium concentration 98 µg/L (IQR 65-365).

PLASMA EXCHANGE

Three patients with stage 5 chronic kidney disease developed aluminium bone disease during plasma exchange; their median blood or serum aluminium concentration was 73 µg/L (IQR 59-81). Asymptomatic aluminium overload was reported in six patients receiving outpatient plasma exchange who had a median creatinine clearance of 71 mL/min (IQR 40-106) and a median aluminium concentration of 49 µg/L (IQR 34-116), and in seven intensive care patients with acute kidney injury whose median aluminium concentration was 30 µg/L (IQR 17-35); (p = 0.02).

INTRAVESICAL EXPOSURES

All 13 intravesical exposures developed aluminium neurotoxicity and had a median aluminium concentration of 157 µg/L (IQR 45-276).

POTABLE WATER

All six patients developed aluminium bone disease and their median blood aluminium concentration was 17 µg/L (IQR 13-100).

CONCLUSIONS

Toxic aluminium exposure can result in neurotoxicity and bone disease, especially in patients with chronic kidney disease. Adults with stage 5 chronic kidney disease chronically exposed to aluminium developed aluminium neurotoxicity at higher concentrations than those with aluminium bone disease or with asymptomatic aluminium overload. Aluminium neurotoxicity was reported at lower concentrations following acute exposure to intravesical aluminium. Extrapolating the relevance of these concentrations to the general population is problematic in that the data were derived from oncology patients, however, the possibility that aluminium neurotoxicity may occur at concentrations lower that those reported historically in patients with stage 5 chronic kidney disease cannot be excluded.

Intravesical instillation of high molecular weight sodium hyaluronate in radiation-induced cystitis: a prospective pilot study

PURPOSE

To assess the efficacy and safety of intravesical instillation of high molecular weight sodium hyaluronate (HMW-HA) for the treatment of radiation-induced cystitis.

METHODS

This prospective cohort study was conducted in seven centers in France. Eligible patients with radiation-induced cystitis were recruited between April 2020 and March 2021. A sterile disposable 50 ml prefilled solution containing 0.16% (80 mg/50 mL) HMW-HA (INSTYLAN) was instilled weekly into the bladder. The treatment consisted of 6 sessions (V1 to V6). Outcomes were assessed 1 week (V7) and 4 weeks (V8) after the last session and were compared with baseline (V0). The primary endpoint was bladder pain, evaluated by a Questionnaire with 5 closed-ended response options. Secondary endpoints included changes from baseline for hematuria, urinary frequency, and the effect of urgencies on Quality of Life (QoL). Adverse events (AEs) were graded according to the CTCAE 3.0 classification.

RESULTS

A total of 30 participants were enrolled. The Intent-to-Treat analysis showed a significant reduction in pelvic pain intensity (- 45.81%, p < 0.001), hematuria (- 26.87%, p = 0.008), total 24 h voids (- 23.92%, p < 0.001) and the effect of urgencies on QoL (- 33.92%, p < 0.001) at V7. The improvement for each outcome remained stable during the post-therapeutic period between V7 and V8. Bladder instillation therapy was well-tolerated: two treatment-related AEs (6.6%) were reported corresponding to two grade 1 hematuria.

CONCLUSIONS

Intravesical instillation of HMW-HA appears to be effective in the treatment of radiation-induced cystitis. Further comparative studies with longer follow-up are needed to confirm our preliminary results.

Cancer survivorship issues with radiation and hemorrhagic cystitis in gynecological malignancies

PURPOSE

Given that more cancers are being diagnosed earlier and that treatment of cancer is improving, health issues of cancer survivors are becoming more common and apparent. Pelvic radiation therapy for the treatment of gynecological cancers can lead to long-term collateral damage to the bladder, a condition termed radiation cystitis (RC). Late sequelae may take many years to develop and include incontinence and pain as well as hematuria. RC is a rare but potentially life-threatening condition for which there are few management and treatment options.

METHODS

There are limited data in the literature regarding the effects of radiation on the bladder after gynecological cancer therapy and we hereby review the literature on cancer survivorship issues of pelvic radiation for gynecology literature.

RESULTS

Treatment options are available for patients with radiation-induced hemorrhagic cystitis. However, most treatments are risky or only effective for a short timeframe and no therapy is currently available to reverse the disease progress. Furthermore, no standardized guidelines exist describing preferred management options. Common therapies include hyperbaric oxygen therapy, clot evacuation, fulguration, intravesical instillation of astringent agents, and surgery. Novel developing strategies include Botulinum Toxin injections and liposomal-tacrolimus instillations. These treatments and strategies are discussed.

CONCLUSIONS

In this review, we will present current and advanced therapeutic strategies for RC to help cancer survivors deal with long-term bladder health issues.

Aluminum as a toxicant

Although aluminum is the most abundant metal in nature, it has no known biological function. However, it is known that there is a causal role for aluminum in dialysis encephalopathy, microcytic anemia, and osteomalacia. Aluminum has also been proposed to play a role in the pathogenesis of Alzheimer’s disease (AD) even though this issue is controversial. The exact mechanism of aluminum toxicity is not known but accumulating evidence suggests that the metal can potentiate oxidative and inflammatory events, eventually leading to tissue damage. This review encompasses the general toxicology of aluminum with emphasis on the potential mechanisms by which it may accelerate the progression of chronic age-related neurodegenerative disorders.

Low levels of aluminum can lead to behavioral and morphological changes associated with Alzheimer's disease and age-related neurodegeneration

Aluminum (Al) is a very common component of the earth's mineral composition. It is not essential element for life and is a constituent of rather inert minerals. Therefore, it has often been regarded as not presenting a significant health hazard. As a result, aluminum-containing agents been used in the preparation of many foodstuffs processing steps and also in elimination of particulate organic matter from water. More recently, the reduced pH of bodies of water resulting from acid rain has led to mobilization of aluminum-containing minerals into a more soluble form, and these have thus entered residential drinking water resources. By this means, the body burden of aluminum in humans has increased. Epidemiological and experimental findings indicate that aluminum is not as harmless as was previously thought, and that aluminum may contribute to the inception and advancement of Alzheimer's disease. Epidemiological data is reinforced by indications that aluminum exposure can result in excess inflammatory activity within the brain. Activation of the immune system not initiated by an infectious agent, typifies the aging brain and is even more augmented in several neurodegenerative diseases. The origin of most age-related neurological disorders is generally not known but as they are largely not of genetic derivation, their development is likely triggered by unknown environmental factors. There is a growing and consistent body of evidence that points to aluminum as being one such significant influence. Evidence is presented that reinforces the likelihood that aluminum is a factor speeding the rate of brain aging. Such acceleration would inevitably enlarge the incidence of age-related neurological diseases.

Advances in Therapeutic Development for Radiation Cystitis

Radiation treatment for pelvic malignancies is typically associated with radiation injury to urinary bladder that can ultimately lead to radiation cystitis (RC). The late sequelae of radiation therapy may take many years to develop and include bothersome storage symptoms such as hematuria, which may be life-threatening in severe cases of hemorrhagic cystitis. Although no definitive treatment is currently available, various interventions are used for radiation and hemorrhagic cystitis including blood transfusion, bladder irrigation, intravesical instillation of substances such as alum, silver nitrate, prostaglandins or formalin, and fulguration of intravesical bleeding sites and surgery options such as supravesical urinary diversions and cystectomy. Effects of non-surgical treatments for radiation and hemorrhagic cystitis are of modest success and studies are lacking to control the effects caused by RC. When such measures have proven ineffective, use of bladder botulinum toxin injection has been reported. New therapy, such as intravesical immunosuppression with local tacrolimus formulation is being developed for the treatment of radiation hemorrhagic cystitis.

Management of radiation cystitis

Acute radiation cystitis occurs during or soon after radiation treatment. It is usually self-limiting, and is generally managed conservatively. Late radiation cystitis, on the other hand, can develop from 6 months to 20 years after radiation therapy. The main presenting symptom is hematuria, which may vary from mild to severe, life-threatening hemorrhage. Initial management includes intravenous fluid replacement, blood transfusion if indicated and transurethral catheterization with bladder washout and irrigation. Oral or parenteral agents that can be used to control hematuria include conjugated estrogens, pentosan polysulfate or WF10. Cystoscopy with laser fulguration or electrocoagulation of bleeding points is sometimes effective. Injection of botulinum toxin A in the bladder wall may relieve irritative bladder symptoms. Intravesical instillation of aluminum, placental extract, prostaglandins or formalin can also be effective. More-aggressive treatment options include selective embolization or ligation of the internal iliac arteries. Surgical options include urinary diversion by percutaneous nephrostomy or intestinal conduit, with or without cystectomy. Hyperbaric oxygen therapy (HBOT) involves the administration of 100% oxygen at higher than atmospheric pressure. The reported success rate of HBOT for radiation cystitis varies from 60% to 92%. An important multicenter, double-blind, randomized, sham-controlled trial to evaluate the effectiveness of HBOT for refractory radiation cystitis is currently being conducted.

Prevention and management of BK-virus associated haemorrhagic cystitis in children following haematopoietic stem cell transplantation--a systematic review and evidence-based guidance for clinical management

Haemorrhagic cystitis (HC) is a common and, in its severe form, potentially life-threatening complication of Haematopoietic stem cell transplantation (HSCT) in children. Recent data indicate an important role of BK virus reactivation during the time of maximal post-transplant immune suppression in the pathogenesis of late-onset HC. Treatment of HC is mainly symptomatic and often frustrating. To give clinicians guidance on prevention and treatment options and their backing by scientific evidence, we have systematically assessed the available literature and devised evidence-based guidelines. Our comprehensive review demonstrates that evidence for the most commonly used interventions (such as cidofovir, oestrogen, hyperbaric oxygen, bladder instillation with formalin, alum salts or prostaglandin) is very limited. Some of these interventions also carry significant risks. Higher level evidence exists only for 2-mercaptoethane sodium (MESNA) and hyperhydration as a preventative intervention, and for systemic recombinant Factor VII as a treatment to stop acute haemorrhage. Further high-quality studies are required to establish effective and safe prevention and treatment options for HC.

Aluminum citrate uptake by immortalized brain endothelial cells: implications for its blood-brain barrier transport

The objective was to further test the hypothesis that aluminum (Al) citrate transport across the blood-brain barrier is mediated by a monocarboxylate transporter (MCT). Speciation calculations showed that Al citrates were the predominant Al species under the conditions employed. Al citrate did not inhibit lactate uptake and was not taken up by the rat erythrocyte, suggesting it does not serve as an effective substrate for either MCT1 or the anion exchanger. Studies were conducted with b.End5 cells derived from mouse brain endothelial cells to identify the properties of the carrier(s) mediating Al citrate transport. Western blot analysis of b.End5 cells showed expression of the transferrin receptor and MCT1, but not MCT2 or MCT4. Uptake of Al citrate was approximately 70% faster than citrate. Citrate and Al citrate uptake were sodium independent. Citrate uptake increased at pH 6.9 compared to 7.4, whereas Al citrate uptake did not. Al citrate uptake was reduced by inhibitors of mitochondrial respiration and oxidative phosphorylation, suggesting ATP dependence, but not by ouabain, suggesting no role for Na/K-ATPase. Uptake was not affected by alpha-ketoglutarate or malonate, substrates for the dicarboxylate carrier. Many substrates and inhibitors of MCT1 and organic anion transporters reduced Al citrate uptake into b.End5 cells. BSP and fluorescein, organic anion transporter substrates/inhibitors, inhibited Al citrate uptake. We conclude that Al citrate transport across the blood-brain barrier is carrier-mediated, involving either an uncharacterized MCT isoform expressed in the brain such as MCT7 or MCT8 and/or one of the many members of the organic anion transporting protein family, some of which are known to be expressed at the blood-brain barrier.