Hepatotoxicity and tuberculosis treatment outcomes in chronic liver disease

Background:

The treatment of tuberculosis (TB) is known to cause liver injury, however, there is limited data to guide optimal treatment for patients with chronic liver disease.

Methods:

We undertook a retrospective case series of patients with chronic liver disease and TB disease. The primary objective was to determine if there was a difference in the incidence of drug-induced liver injury (DILI) in patients with cirrhosis versus those with chronic hepatitis. Additionally, we sought to compare TB treatment outcomes, type and duration of therapy, and incidence of adverse events.

Results:

We included 56 patients (chronic hepatitis 40; cirrhosis 16). There were 33 patients (58.9%) who experienced DILI requiring treatment modification, with no significant difference between groups: 65% vs. 43.8%, p = 0.23. Patients with chronic hepatitis were more likely to receive treatment with standard first-line intensive phase therapy that included a combination of rifampin (RIF), isoniazid, and pyrazinamide (80.8% vs. 19.2%, p = 0.03) and any regimen than included isoniazid (92.5% vs. 68.8%, p = 0.04). The risk of DILI was higher when more hepatotoxic TB medications were used. Overall treatment success in this cohort was low (55.4%), with no significant difference between groups (62.5% vs. 37.5%, p = 0.14). Most patients with treatment success (97%) were able to tolerate a rifamycin.

Conclusions:

The risk of DILI is high, especially with the use of isoniazid, in patients with TB and chronic liver disease. This risk can be effectively mitigated with no difference in treatment outcomes in the presence of cirrhosis.

The Struggle to End a Millennia-Long Pandemic: Novel Candidate and Repurposed Drugs for the Treatment of Tuberculosis

This article provides an encompassing review of the current pipeline of putative and developed treatments for tuberculosis, including multidrug-resistant strains. The review has organized each compound according to its site of activity. To provide context, mention of drugs within current recommended treatment regimens is made, thereafter followed by discussion on recently developed and upcoming molecules at established and novel targets. The review is designed to provide a clinically applicable understanding of the compounds that are deemed most currently relevant, including those already under clinical study and those that have shown promising pre-clinical results. An extensive review of the efficacy and safety data for key contemporary drugs already incorporated into treatment regimens, such as bedaquiline, pretomanid, and linezolid, is provided. The three levels of the bacterial cell wall (mycolic acid, arabinogalactan, and peptidoglycan layers) are highlighted and important compounds designed to target each layer are delineated. Amongst others, the highly optimistic and potent anti-mycobacterial activity of agents such as BTZ-043, PBTZ 169, and OPC-167832 are emphasized. The evolving spectrum of oxazolidinones, such as sutezolid, delpazolid, and TBI-223, all aiming to exceed the efficacy achieved with linezolid yet offer a safer alternative to the potential toxicity, are reviewed. New and exciting prospective agents with novel mechanisms of impact against TB, including 3-aminomethyl benzoxaboroles and telacebec, are underscored. We describe new diaryloquinolines in development, striving to build on the immense success of bedaquiline. Finally, we discuss some of these compounds that have shown encouraging additive or synergistic benefit when used in combination, providing some promise for the future in treating this ancient scourge.

Lymphocutaneous spread of Mycobacterium elephantis in an immunocompetent individual: A case report

Mycobacterium elephantis was first described when isolated from an elephant that succumbed to lung abscess. However, despite this namesake, it is not associated with animals and has been described most often as a probable colonizer rather than pathogen in humans with chronic lung disease. In this report, we describe the first case of lymphocutaneous infection from M. elephantis, likely as a result of cutaneous inoculation with contaminated soil. This offers further evidence to its capabilities as a pathogen. We provide a review of the limited prior reports of M. elephantis and outline the available in vitro data on efficacy of various antimycobacterial agents.

Assessing the efficacy and safety of hydroxychloroquine as outpatient treatment of COVID-19: a randomized controlled trial

BACKGROUND

Identification of therapies to prevent severe COVID-19 remains a priority. We sought to determine whether hydroxychloroquine treatment for outpatients with SARS-CoV-2 infection could prevent hospitalization, mechanical ventilation or death.

METHODS

This randomized controlled trial was conducted in Alberta during the first wave of the COVID-19 pandemic without direct contact with participants. Community-dwelling individuals with confirmed SARS-CoV-2 infection (by reverse transcription polymerase chain reaction [RT-PCR] viral ribonucleic acid test) within the previous 4 days, and symptom onset within the previous 12 days, were randomly assigned to oral hydroxychloroquine or matching placebo for 5 days. Enrolment began Apr. 15, 2020. The primary outcome was the composite of hospitalization, invasive mechanical ventilation or death within 30 days. Secondary outcomes included symptom duration and disposition at 30 days. Safety outcomes, such as serious adverse events and mortality, were also ascertained. Outcomes were determined by telephone follow-up and administrative data.

RESULTS

Among 4919 individuals with a positive RT-PCR test, 148 (10.2% of a planned 1446 patients) were randomly assigned, 111 to hydroxychloroquine and 37 to placebo. Of the 148 participants, 24 (16.2%) did not start the study drug. Four participants in the hydroxychloroquine group met the primary outcome (4 hospitalizations, 0 mechanical ventilation, 4 survived to 30 days) and none in the placebo group. Hydroxychloroquine did not reduce symptom duration (hazard ratio 0.77, 95% confidence interval 0.49-1.21). Recruitment was paused on May 22, 2020, when a since-retracted publication raised concerns about the safety of hydroxychloroquine for hospitalized patients with COVID-19. Although we had not identified concerns in a safety review, enrolment was slower than expected among those eligible for the study, and cases within the community were decreasing. Recruitment goals were deemed to be unattainable and the trial was not resumed, resulting in a study underpowered to assess the effect of treatment with hydroxychloroquine and safety.

INTERPRETATION

There was no evidence that hydroxychloroquine reduced symptom duration or prevented severe outcomes among outpatients with proven COVID-19, but the early termination of our study meant that it was underpowered.

TRIAL REGISTRATION

ClinicalTrials.gov, no. NCT04329611.

Rifampin-resistant/multidrug-resistant Tuberculosis in Alberta, Canada: Epidemiology and treatment outcomes in a low-incidence setting

Treatment of rifampin-monoresistant/multidrug-resistant Tuberculosis (RR/MDR-TB) requires long treatment courses, complicated by frequent adverse events and low success rates. Incidence of RR/MDR-TB in Canada is low and treatment practices are variable due to the infrequent experience and challenges with drug access. We undertook a retrospective cohort study of all RR/MDR-TB cases in Alberta, Canada from 2007-2017 to explore the epidemiology and outcomes in our low incidence setting. We performed a descriptive analysis of the epidemiology, treatment regimens and associated outcomes, calculating differences in continuous and discrete variables using Student's t and Chi-squared tests, respectively. We identified 24 patients with RR/MDR-TB. All patients were foreign-born with the median time to presentation after immigration being 3 years. Prior treatment was reported in 46%. Treatment was individualized. All patients achieved sputum culture conversion within two months of treatment initiation. The median treatment duration after culture conversion was 18 months (IQR: 15-19). The mean number of drugs utilized during the intensive phase was 4.3 (SD: 0.8) and during the continuation phase was 3.3 (SD: 0.9) and the mean adherence to medications was 95%. Six patients completed national guideline-concordant therapy, with many patients developing adverse events (79%). Treatment success (defined as completion of prescribed therapy or cure) was achieved in 23/24 patients and no acquired drug resistance or relapse was detected over 1.8 years of median follow-up. Many cases were captured upon immigration assessment, representing important prevention of community spread. Despite high rates of adverse events and short treatment compared to international guidelines, success in our cohort was very high at 96%. This is likely due to individualization of therapy, frequent use of medications with high effectiveness, intensive treatment support, and early sputum conversion seen in our cohort. There should be ongoing exploration of treatment shortening with well-tolerated, efficacious oral agents to help patients achieve treatment completion.

Asymmetric eye size in an infant

Toxoplasmosis is an uncommon congenital infection in Canada, but one with potentially severe clinical manifestations, including fetal death. Neurologic and ocular manifestations are frequent in untreated disease; however, small eye size (microphthalmia) is a rare finding. This finding may be a marker of severe ocular disease. As universal screening does not occur in Canada, clinicians' early recognition is imperative, particularly given the lack of risk factors in many patients and the benefit that treatment may have even in initially asymptomatic disease. Here, we report a case of congenital toxoplasmosis and review the diagnostics and treatment of the infection.

Epidemiology of E. coli in Cystic Fibrosis Airways Demonstrates the Capacity for Persistent Infection but Not Patient-Patient Transmission

Escherichia coli is frequently isolated from the respiratory secretions of cystic fibrosis (CF) patients yet is not considered a classical CF pathogen. Accordingly, little is known about the natural history of this organism in the CF airways, as well as the potential for patient-to-patient transmission. Patients attending the Calgary Adult CF Clinic (CACFC) between January 1983 and December 2016 with at least one E. coli-positive sputum culture were identified by retrospective review. Annual E. coli isolates from the CACFC biobank from each patient were typed by pulsed-field gel electrophoresis (PFGE) and isolates belonging to shared pulsotypes were sequenced. Single nucleotide polymorphism (SNP) and phylogenetic analysis were used to investigate the natural history of E. coli infection and identify potential transmission events. Forty-five patients with E. coli-positive sputum cultures were identified. Most patients had a single infection episode with a single pulsotype, while replacement of an initial pulsotype with a second was observed in three patients. Twenty-four had E. coli recovered from their sputum more than once and 18 patients had persistent infections (E. coli carriage >6 months with ≥3 positive cultures). Shared pulsotypes corresponded to known extraintestinal pathogenic E. coli strains: ST-131, ST-73, and ST-1193. Phylogenetic relationships and SNP distances among isolates within shared pulsotypes were consistent with independent acquisition of E. coli by individual patients. Most recent common ancestor date estimates of isolates between patients were inconsistent with patient-to-patient transmission. E. coli infection in CF is a dynamic process that appears to be characterized by independent acquisition within our patient population and carriage of unique sets of strains over time by individual patients.

Incidence, treatment, and outcomes of isoniazid mono-resistant Mycobacterium tuberculosis infections in Alberta, Canada from 2007-2017

Isoniazid resistant Mycobacterium tuberculosis (Hr-TB) is the most frequently encountered TB resistance phenotype in North America but limited data exist on the effectiveness of current therapeutic regimens. Ineffective treatment of Hr-TB increases patient relapse and anti-mycobacterial resistance, specifically MDR-TB. We undertook a multi-centre, retrospective review of culture-positive Hr-TB patients in Alberta, Canada (2007-2017). We assessed incidence and treatment outcomes, with a focus on fluoroquinolone (FQ)-containing regimens, to understand the risk of unsuccessful outcomes. Rates of Hr-TB were determined using the mid-year provincial population and odds of unsuccessful treatment was calculated using a Fisher's Exact test. One hundred eight patients of median age 37 years (IQR: 26-50) were identified with Hr-TB (6.3%), 98 of whom were able to be analyzed. Seven percent reported prior treatment. Rate of foreign birth was high (95%), but continent of origin did not predict Hr-TB (p = 0.47). Mean compliance was 95% with no difference between FQ and non-FQ regimens (p = 1.00). Treatment success was high (91.8%). FQ-containing regimens were frequently initiated (70%), with no difference in unsuccessful outcomes compared to non-FQ-containing regimens (5.8% vs. 13.8%, OR 0.4, 95% CI 0.1-2.3, p = 0.23). Only one patient (1%) utilizing a less common non-FQ-based regimen including two months of pyrazinamide developed secondary multidrug resistance. Unsuccessful treatment was low (<10%) relative to comparable literature (~15%) and showed similar outcomes for FQ and non-FQ-based regimens and no deficit to those using intermittent fluoroquinolones in the continuation phase of treatment. Our findings are similar to recent data, however prospective, randomized trials of adequate power are needed to determine the optimal treatment for Hr-TB.

Clinical Outcomes Associated With Escherichia coli Infections in Adults With Cystic Fibrosis: A Cohort Study

Background

Analysis of “emerging” pathogens in cystic fibrosis (CF) lung disease has focused on unique pathogens that are rare in other human diseases or are drug resistant. Escherichia coli is recovered in the sputum of up to 25% of patients with CF, yet little is known about the epidemiology or clinical impact of infection.

Methods

We studied patients attending a Canadian adult CF clinic who had positive sputum cultures for E coli from 1978 to 2016. Infection was categorized as transient or persistent (≥3 positive sputum cultures, spanning >6 months). Those with persistent infection were matched 2:1 with age, sex, and time-period controls without history of E coli infection, and mixed-effects models were used to assess pulmonary exacerbation (PEx) frequency, lung function decline, hospitalization, and intravenous antibiotic days.

Results

Forty-five patients (12.3%) had E coli recovered from sputum samples between 1978 and 2016, and 18 patients (40%) developed persistent infection. Nine patients (24%) had PEx at incident infection, and increased bioburden was predictive of exacerbation (P = .03). Risk factors for persistent infection included lower nutritional status (P < .001) and lower lung function (P = .009), but chronic infection with Pseudomonas aeruginosa was protective. There was no difference in annual lung function decline, need for hospitalization or intravenous antibiotics, or risk of PEx in patients with persistent infection.

Conclusions

Persistent E coli infection was frequent and was more common in CF patients with low nutritional status and lung function. However, this does not predict clinical decline. Multicenter studies would allow better characterization of the epidemiology and clinical impact of E coli infection.

Prosthetic joint and implant contamination caused by Ralstonia pickettii: a report of three cases٭

We describe three cases of orthopaedic contamination caused by Ralstonia pickettii grown from prosthetic joint and implant material cultures following sonication in the microbiology laboratory. Given the temporal association between the cases, lack of clinical or intra-operative features of infection, growth of the organism in the water bath, and unlikely etiology of Ralstonia as a prosthetic joint or implant pathogen, the bacteria were judged to be contaminants.

Effect of low-dose cyclosporin on plasma lipoproteins and markers of cholestasis in patients with psoriasis

The benefits of using cyclosporin in organ transplantation to prevent graft rejection outweigh its potential disadvantages, but with the use of low-dose cyclosporin in relatively healthy individuals, such as those with psoriasis, the risk:benefit ratio is altered. The effects of low-dose cyclosporin (< 5 mg/kg body weight) on liver function and serum lipids and lipoproteins were examined in 40 normolipidaemic, normotensive psoriasis patients with normal renal function. After 3 months of treatment, serum cholesterol and bilirubin concentrations and alkaline phosphatase activity increased significantly (p = 0.001), and glomerular filtration rate (GFR) declined from 107 to 96 ml/min/1.73 m2 (p = 0.05). All these values returned to pretreatment levels 3 months after cessation of cyclosporin. In 15 patients in whom lipoproteins were isolated by ultracentrifugation, there was an increase in plasma low-density lipoprotein (LDL) cholesterol (p = 0.05), but very-low-density lipoprotein cholesterol, high-density lipoprotein (HDL) and HDL2 and HDL3 cholesterol concentrations did not change. The increases in serum bilirubin, alkaline phosphatase activity and LDL cholesterol, seen in individuals with normal baseline liver and renal function, which reverted to baseline following cessation of cyclosporin, suggest that cyclosporin-induced hypercholesterolaemia may be due to either decreased biliary excretion of cholesterol or impaired catabolism of LDL.

Angiotensin II as a risk factor for cyclosporin nephrotoxicity in patients with psoriasis

Abnormalities of the renin-angiotensin system after low-dose cyclosporin (5 mg/kg/day or less) have not been adequately defined in patients with normal kidneys. 27 patients with psoriasis were assessed before starting cyclosporin, after three months of cyclosporin (5 mg/kg/day or less) and then finally three months after finishing cyclosporin. On each occasion plasma renin activity (PRA), aldosterone, angiotensin II and atrial natriuretic peptide (ANP) were measured together with total renal blood flow (RBF), GFR and filtration fraction (FF) following an i.v. bolus injection of Tc-99m DTPA. Significant renal hemodynamic toxicity was defined as > 25% fall in RBF or > 20% fall in GFR. Using these criteria we identified 12 patients with hemodynamic toxicity (Group A) and 15 patients whose GFR and RBF did not fall significantly (Group B). In Group A a significant fall in GFR (p < 0.001) and reduction in renal blood flow (p < 0.04) were associated with significant rises in both ambulant and recumbent angiotensin II (p < 0.0005). PRA, aldosterone and ANP did not significantly alter. GFR partially recovered after withdrawal of cyclosporin although RBF remained significantly lower compared to initial values. In Group B there was no significant change in GFR or RBF although there was a reversible fall in FF (p < 0.02). There were no significant differences in angiotensin II, PRA, aldosterone or ANP. Circulating angiotensin II rises in patients who develop cyclosporin nephrotoxicity and may be responsible for mediating the hemodynamic effects.

Cyclosporin A and vitamin D metabolism: studies in patients with psoriasis and in rats

1. Cyclosporin A, an immunosuppressive drug used to treat psoriasis, stimulates renal synthesis of 1,25-dihydroxyvitamin D in rats. 1,25-Dihydroxyvitamin D can also reduce the activity of psoriasis, and in the present study we have examined the possibility that cyclosporin A mediates some of its actions in psoriasis by renal or extra-renal production of 1,25-dihydroxyvitamin D. 2. Treatment of 12 psoriatic patients with cyclosporin A (5 mg day-1 kg-1) for 3 months significantly improved the psoriasis activity and severity index and reduced glomerular filtration rate, but serum 1,25-dihydroxyvitamin D levels were not changed. However, 1-3 months after stopping cyclosporin A treatment, an increase in the psoriasis activity and severity index score was accompanied by a small, but significant, increase in serum 1,25-dihydroxyvitamin D concentration. Plasma 1,25-dihydroxyvitamin D levels in rats gavaged with cyclosporin A (15 mg day-1 kg-1 for 2 weeks) were significantly increased compared with controls, but a lower dose of cyclosporin A (2.4 mg day-1 kg-1) had no effect. Renal 25-hydroxyvitamin D-24-hydroxylase activity in rat kidney homogenates was not different between control and cyclosporin A-treated rats. Renal 25-hydroxyvitamin D-1 alpha-hydroxylase activity was not detectable in these homogenates. Extra-renal production of 1,25-dihydroxyvitamin D by activated macrophages isolated from the synovial fluid of patients with inflammatory arthritis was reduced after incubation with cyclosporin A (0.1-10 mumol/l) for 30 h or 5 days.(ABSTRACT TRUNCATED AT 250 WORDS)

Renal function does not always predictably deteriorate in blind insulin-dependent diabetics with nephropathy

Two insulin-dependent diabetic women with severe retinopathy who were referred for the management of nephrotic syndrome are presented. On the basis of clinical risk factors, such as retinopathy and severe hypertension, both patients were expected to develop progressive end-stage renal failure. One woman has shown a gradual decline in creatinine clearance over 7 years while the plasma creatinine of the other has remained normal for 11 years. The unexpectedly good outcome of both these patients may be related to maintaining a normal blood pressure despite neither patient receiving a prolonged course of an angiotensin-converting enzyme inhibitor. Because of the efficacy of current antihypertensive therapy, the outcome of diabetic nephropathy cannot be so easily predicted and needs to be formally reassessed.

Altered clearance of N-1 methylnicotinamide associated with the use of low doses of cyclosporine

To improve the monitoring of patients on low doses of cyclosporine there is a need for new tests of tubular function. N-1 methylnicotinamide (NMM) is an endogenous organic cation that is secreted by the proximal tubule and its clearance can be measured. In 27 patients with psoriasis, serial measurements of NMN clearance, plasma aldosterone, plasma chloride, bicarbonate, and magnesium were compared with changes in the radionuclide measurement of glomerular filtration rate and renal blood flow before, during, and after a 3-month course of low-dose cyclosporine (< 5 mg/kg/d). N-1 methylnicotinamide clearance decreased significantly with cyclosporine only (2.5 mg/kg/d, n = 10, P < 0.01). Recovery of NMN clearance lagged behind that of glomerular filtration rate and renal blood flow. Serum magnesium decreased significantly on cyclosporine (2.5 mg/kg, n = 10, P < 0.01; 5 mg/kg, n = 9, P < 0.0001). In the whole group, plasma potassium increased significantly (n = 27, P < 0.02) and plasma aldosterone was inappropriately low. Low doses of cyclosporine in psoriasis cause a reduced clearance of NMN, hypomagnesemia, and a variable hyperchloremic acidosis. Nifedipine may alter these biochemical variables without necessarily improving renal hemodynamics. The delayed recovery of NMN clearance in comparison with renal haemodynamic measurements following cyclosporine therapy suggests that this noninvasive test of tubular function may be a marker of persisting cyclosporine nephrotoxicity and that it should be evaluated further.

Changes in numbers of epidermal cell adhesion molecules caused by oral cyclosporin in psoriasis

AIM

To determine the effects of a three month course of low dose cyclosporin on the expression of epidermal cell adhesion molecules.

METHODS

Eighteen patients with psoriasis were treated for 12 weeks with either 2.5 or 5 mg/kg/day of oral cyclosporin. Biopsy specimens taken from skin before, during, and after cyclosporin treatment were stained immunohistochemically for CD 54 (ICAM-1), CD 29 (beta-1 integrins), and CD18 (beta-2 integrins).

RESULTS

There was a highly significant (p < 0.01) clinical response after 12 weeks of cyclosporin as assessed by the Psoriasis Area and Severity Index (PASI) score. The staining of CD 29 on keratinocytes of affected and unaffected psoriatic skin was not affected by cyclosporin. Epidermal CD54 was variably expressed in active psoriatic plaques and changed unpredictably after cyclosporin (p = NS). Staining for CD18 on large epidermal dendritic cells was reduced after cyclosporin (p < 0.02). The expression of CD18 by large epidermal dendritic cells during treatment correlated strongly with the PASI score at that time and one month after stopping cyclosporin (p < 0.02).

CONCLUSIONS

Persistence of epidermal staining for CD 54 in psoriasis is compatible with a good clinical response to cyclosporin. Residual staining for CD 18 on large epidermal dendritic cells may be a useful marker for early clinical relapse.

A quantitative immunohistochemical study of the expression of integrins by nerves in psoriatic and normal skin

Qualitative and quantitative assessment of integrin expression by dermal nerves was made by an avidin-biotin immunoperoxidase method on snap-frozen biopsies from affected psoriatic skin, and skin from normal control subjects with no history of skin disease. Nerves expressed alpha 1, alpha 2, alpha 3, alpha 6, beta 1 and beta 4 integrin subunits, and perineural sheaths in the mid-dermis also expressed these subunits, with the exception of alpha 2. There were more upper dermal nerve segments expressing alpha 1 integrin compared with other integrins both in controls and in psoriatic skin. The greater number of nerves expressing alpha 1 integrin compared with other integrins may be due to anatomical or functional differences between groups of nerves. There were significantly more nerves expressing alpha 1, alpha 2, alpha 3, alpha 6 and beta 4 integrins in psoriatic skin compared with control skin. This generalized increase may indicate a secondary trophic effect on all nerves rather than a specific increase in one type of nerve. However, the expression of alpha 2 integrin may be significant in the pathogenesis of the psoriatic plaque, in that it was barely detectable in the normal site-matched biopsies, but much greater in psoriatic plaques. The study of the expression of adhesion molecules by neurones in psoriasis offers a new avenue for investigation of the role of neuronal hypertrophy in the initiation and maintenance of psoriatic plaques.

Disturbance in renal haemodynamics and physiology in bone marrow transplant recipients treated with ciclosporin A

The vascular disturbance associated with ciclosporin (CS) nephrotoxicity is poorly defined in both the normal and transplanted human kidney. Six bone marrow transplant recipients were studied before, during and after administration of CS. By analysis of time activity curves and clearance of Tc-99m DTPA, renal blood flow (RBF), filtration fraction (FF) and GFR were shown to fall on CS (GFR: p less than 0.001; RBF, FF: p less than 0.01). These haemodynamic variables did not fully recover with dose reduction or after discontinuation of therapy. Plasma renin activity (PRA) aldosterone and atrial natriuretic peptide did not change although there appeared a tendency for PRA to fall on CS. There was a reversible normokalemic metabolic acidosis. CS levels stayed within the therapeutic range. The partial reversibility of GFR, RBF and FF is consistent with CS-induced functional disturbance and reflects sensitivity to microvascular and tubular injury of the normal human kidney.

Cyclosporin A does not possess K+ channel opening properties in smooth muscle

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A new syndrome of autosomal recessive nephropathy, deafness, and hyperparathyroidism

A consanguineous Pakistani family is described in which family members developed renal failure without haematuria, parathyroid hyperplasia, and sensorineural deafness. We believe the condition to be inherited as an autosomal recessive and to be distinct from Alport's syndrome, which is an X linked condition usually associated with haematuria.

Chyluria as a cause of haematuria in patients from endemic areas

Chyluria is an unusual cause of haematuria in temperate regions and is rarely considered even when no apparent cause has been found. We report 3 Guyanese men who presented with macroscopic haematuria in whom pyelo-lymphatic fistulae were found. In none of the patients were the symptoms severe enough for surgical disconnection of the fistula to be required.