Haematological and biochemical alterations in leprosy patients already treated with dapsone and MDT

Dapsone (DDS) is useful in the treatment of a number of inflammatory conditions which are characterized by neutrophil infiltration. It is the drug of choice for the treatment of leprosy and prophylaxis of malaria. Haematological side effects of methaemoglobinaemia and haemolysis have been long recognized. However, the frequency and severity of these side effects in patients already treated with DDS as a single drug or as part of a multidrug therapy (MDT) have not been well documented. We report herein an investigation of the effect of dapsone long-term treatment on the haematological and biochemical alterations in leprosy patients undergoing dapsone as a single drug (DDS group) or as part of a multidrug therapy in combination with rifampin and clofazimine (MDT group). Methaemoglobinaemia and haemolytic anaemia were the principal side effects observed. Reticulocytes were found to be elevated (> 1.5%) in 90% of the patients. Heinz bodies were also detected (6.6% of the patients). The osmotic fragility test showed a reduction in cell resistance and in the evaluation of white cells a severe eosinophilia was found. Hepatic, pancreatic and renal evaluation by the determination of biochemical parameters showed rare and occasional changes of no apparent clinical significance. We conclude that haematological side effects of dapsone are significant even at doses currently used to treat leprosy (100 mg/day) and that rifampin and clofazimine do not increase the incidence of these effects during long-term treatment.

Influence of acetylator phenotype on the haematological and biochemical effects associated with dapsone in leprosy patients

Methaemoglobinaemia and haemolytic anaemia were the principal side-effects observed in 30 leprosy patients undergoing long-term treatment with dapsone as a single drug or as part of multidrug therapy. Hepatic, pancreatic and renal evaluations showed no relevant clinical changes. Since N-acetylation is a major metabolic pathway for dapsone, slow acetylation phenotype may be a risk factor for the development of these reactions. To confirm this hypothesis we correlated acetylator phenotype and the haematological and biochemical effects induced by dapsone. No excess proportion of slow acetylators was found. We conclude that slow acetylators are not at greater risk of developing haematological side-effects of dapsone than fast acetylators.

Daily multidrug therapy for leprosy; results of a fourteen-year experience

Between 1980 and 1994, 67 new or relapsing leprosy patients were treated by daily administered multidrug regimens. Tuberculoid patients (23 TT/BT) received either bitherapy [rifampin + dapsone or clofazimine (RMP + DDS or CLO)] or tritherapy [RMP + DDS and/or CLO and/or ethionamide (ETH)] until clinical cure. Lepromatous patients (44 BB/BL/LL) received tritherapy (RMP + DDS and/or CLO and/or ETH) at least until bacteriological negativity. Of the 23 tuberculoid patients only one patient (5%) was cured at 6 months and about 70% needed between 6 and 24 months of treatment to obtain clinical cure (mean 19.5 months). In the 44 lepromatous patients, the achievement of bacteriological negativity was significantly linked to the initial bacterial index (BI), and it occurred after 2 to 7 years (mean 66.5 months) of multidrug therapy (MDT). The average BI decrease per year was 1.1+ during the first year, 0.9+ the second year, and then < 0.5+ per year. Reactional states significantly (p < 0.01) influenced the BI course: reversal reactions (RR) accelerated while erythema nodosum leprosum (ENL) delayed the BI decrease. Three of the 23 (13%) tuberculoid and 19 of the 44 (43%) lepromatous patients (p < 0.02) exhibited a RR and 18 of 44 (41%) lepromatous patients had ENL during MDT. A late RR (LRR) was observed in 1 (5%) and 6 (17%) of our tuberculoid and lepromatous patients, respectively, and 3 (8%) of our lepromatous patients suffered post-MDT ENL. No confirmed relapse has been observed within a follow-up period of 6 months to 7 years and 3 months [59 person-years at risk (PYR)] for TT/BT patients and of 4 months to 5 years and 10 months (100 PYR) for BB/BL/LL patients. When compared to the recommended WHO/MDT, it appears that daily MDT does not increase the clinical or the bacteriological cure rates either at 6 months in paucibacillary tuberculoid patients or at 2d years in multibacillary lepromatous patients. Moreover, as does the WHO/MDT, our regimens show a high frequency of reactional states both during and after treatment. This fact constitutes the main new problem of the actual treatment of leprosy.

Treatment of localized Mycobacterium avium complex infection with clofazimine and doxycycline in a cat

Mycobacterium avium complex infection resulted in a granuloma that developed at the base of the left ear in a cat. The lesion caused vestibular dysfunction and facial palsy on the left side and protruded into the oral cavity on that side. The cat was treated successfully, with resolution of the lesion and elimination of the organism, by use of combined administration of clofazimine and doxycycline. Adverse effects of the clofazimine treatment included temporary reddish-orange discoloration of the cat's skin and mucous membranes.

Clofazimine induced cardiotoxicity--a case report

A 66-year-old Indian male who had been treated for recurrent erythema nodosum leprosum with 300 mg of clofazimine per day for 11 months presented to hospital with a 4 week history of severe gastrointestinal upset. Soon after admission he developed several short runs of ventricular tachycardia with a morphology suggestive of torsade de pointe. The patient had a slightly low magnesium level which was corrected within 2 days; however, his rhythm disturbance persisted for 5 days despite management with intravenous lidocaine. His gastrointestinal symptoms abated 2 weeks after clofazimine was discontinued. Subsequent investigations showed that the patient had a keratopathy and myelin-type figures in his polymorphonuclear white cells similar to that seen with the cardiotoxic drugs chloroquine and amiodarone. It is postulated that clofazimine alone or in conjunction with electrolyte disturbance was responsible for the patient's cardiac arrythmia.

Clofazimine: a review of its medical uses and mechanisms of action

Clofazimine has been in clinical use for almost 40 years, but little is known of its mechanism of action. The primary indication for clofazimine is multibacillary leprosy, but it is useful in several infectious and noninfectious diseases, such as typical myocobacterial infections, rhinoscleroma, pyoderma gangrenosum, necrobiosis lipoidica, severe acne, pustular psoriasis, and discoid lupus erythematosus. Postulated mechanisms of action include intercalation of clofazimine with bacterial DNA and increasing levels of cellular phospholipase A2. Clinical experience, possible mechanisms of action, and side effects of clofazimine are summarized.

The individual microbiologic effect of three antimycobacterial agents, clofazimine, ethambutol, and rifampin, on Mycobacterium avium complex bacteremia in patients with AIDS

The individual antibacterial activities of clofazimine, ethambutol, and rifampin in the treatment of Mycobacterium avium complex bacteremia in patients with AIDS were determined. Sixty human immunodeficiency virus 1-infected patients who had at least one blood culture positive for M. avium complex were randomized to receive either clofazimine (200 mg), ethambutol (15 mg/kg), or rifampin (600 mg) once daily for 4 weeks. Only ethambutol resulted in a statistically significant reduction in the level of mycobacteremia. The median change in individual baseline colony counts was -0.60 log10 cfu/mL after 4 weeks of ethambutol (P = .046). In contrast, median changes in individual baseline colony counts were -0.2 log10 cfu/mL and +0.2 log10 cfu/mL for clofazimine and rifampin, respectively (both, P > .4). Ethambutol had greater antibacterial activity, as determined by changes in the level of mycobacteremia, than either rifampin or clofazimine, supporting its continued use in combination with other agents in the treatment of M. avium infection.

Clinical trial of ofloxacin alone and in combination with dapsone plus clofazimine for treatment of lepromatous leprosy

Twenty-four patients with newly diagnosed lepromatous leprosy were allocated randomly to three groups and treated for 56 days with 400 mg of ofloxacin daily, 800 mg of ofloxacin daily, or 400 mg of ofloxacin, 100 mg of dapsone, and 50 mg of clofazimine daily plus 300 mg of clofazimine once every 28 days. The patients in all three groups demonstrated remarkable clinical improvements, accompanied by rapid decline of the morphological index in skin smears during treatment. More than 99, > 99.99, and > 99.99% of the viable Mycobacterium leprae organisms had been killed by 14, 28, and 56 days of treatment, respectively, as measured by inoculation into the footpads of immunocompetent and nude mice of organisms recovered from skin biopsy specimens obtained before and during treatment. Mild to moderate elevations of the serum glutamic pyruvic transaminase level were observed in four patients, all after 28 days of treatment, which returned to normal after the trial had been completed. Clinical improvement, bactericidal activity, and hepatotoxicity did not differ significantly among the three groups. Ofloxacin displayed powerful bactericidal activity against M. leprae in leprosy patients and may be an important component of new multidrug regimens for the treatment of leprosy. Its optimal dosage appears to be 400 mg daily, and combination with dapsone and clofazimine does not enhance its activity.

Lymphangiographic evaluation of patients with clinical lepromatous leprosy on clofazimine

Pedal edema as a possible adverse effect of clofazimine therapy in leprosy was first reported in 1990. Raasch, et al. reported their lymphangiographic findings on ten patients who had clinical lepromatous leprosy in 1969. None of these patients had been on clofazimine therapy. Our study, therefore, was designed to assess the changes that might be seen in the lymphatic system of patients treated with clofazimine for the management of leprosy. Our findings are compared with those of Raasch and his colleagues.

[Idiopathic pustular and bullous variants of Sweet syndrome]

We report on the case of a 62-year-old patient with disseminated pustular plaques affecting especially his face and hands. These lesions exhibited severe blistering later in the course. The diagnosis of an unusual variant of an acute febrile neutrophilic dermatosis (Sweet's syndrome) was histologically confirmed. Pustular lesions are known to occur in Sweet's syndrome. Secondary development into bullous lesions, however, has not previously been described. No associated disease has so far been detected.

[Mycobacterium avium intracellulare infections. Treatment with a clarithromycin-clofazimine combination. 18 cases]

Infections caused by Mycobacterium avium intracellulare have become worrying because of their higher frequency, their new tendency to diffuse in all tissues (notably the blood) and the lack of curative treatment. The mortality rate remains high and the survival of patients after AIDS is diagnosed is estimated at 7.4 months. The effectiveness of new antimycobacterial drugs, observed in experiments on beige mice, has not yet been confirmed. In 18 patients suffering from this infection, either disseminated (88 percent) or localized in the lung (12 percent), a 12-week treatment with the clarithromycin-clofazimine combination has succeeded in sterilizing the pathological samples. Most patients reported a distinct improvement in their general condition, with fall of temperature, disappearance of most other symptoms, weight gain and better quality of life. Treatment was interrupted in 1 patient owing to liver toxicity. In this study the median survival of the patients after the Mycobacterium avium complex has been estimated at 11.4 months after the diagnosis of AIDS at 28.9 months.

Efficacy and safety of multidrug therapy in paucibacillary leprosy in Singapore

A total of 49 patients with paucibacillary leprosy (PB) who completed multidrug therapy (MDT) between 1985 and 1990 were analysed retrospectively for efficacy and complications; 20 (40.8%) patients had borderline-tuberculoid (BT), 13 (26.5%) had tuberculoid (TT), 1 (2.1%) had indeterminate (I) and 15 (30.0%) had pure neural (N) leprosy; 26 patients (76.5% of 34 non-neural leprosy) were skin biopsied for histological cure before MDT was stopped. Of these 26 patients, 19 had histological clearance at 6 months while the remaining 7 cleared beyond 1 year (18-36 months). The remaining 8 non-neural patients who refused rebiopsy had MDT for 6-8 months and the MDT was stopped when there was clinical clearance. Of the 15 neural (N) leprosy patients, 11 were given MDT for 6 months while the rest had 12-18 months of treatment; 1 patient with neural leprosy, who was treated for 6 months, relapsed with BT leprosy 18 months post-treatment. There were few complications among the 49 patients-4 (8.2%) patients developed reaction to dapsone, 1 (2.0%) had the dapsone syndrome, 2 (4.1%) had haemolytic anaemia and 1 (2.0%) had dapsone hepatitis; 7 (14.3%) patients had type I reaction.

Comparative study of short term results in two multidrug regimens in multibacillary leprosy

Thirty lepromatous and Borderline lepromatous leprosy patients were treated with multidrug therapy in an open trial. Fifteen of them received the standard WHO multidrug regimen ie., rifampicin 600 mg and clofazimine 300 mg monthly, supervised, and dapsone 100 mg daily and clofazimine 100 mg on alternate days as self administered; the other 15 received a modified multidrug therapy regimen comprising of rifampicin 600 mg, clofazimine 100 mg and dapsone 100 mg daily for 21 days as suggested by the Indian Association of Leprologists, followed by the standard WHO regimen. The observation period was six months. Clinical, bacteriological, histological and immunological parameters were studied. The fall in morphological index was much faster in patients receiving modified multidrug therapy regimen compared to those receiving the standard WHO regimen. Otherwise, there was no difference between the two groups of patients. Five patients developed type I (upgrading) reaction with one developing ulnar nerve paralysis. No untoward effects of drugs were noted in the study subjects except for darkening of skin colour of all the patients.

Severe abdominal pain in low dosage clofazimine

We describe a 41 yr old leprosy patient treated for 10 yrs with clofazimine who underwent laparotomy for severe abdominal pain. At surgery, the only significant findings were that the coeliac lymph nodes were enlarged and stained purplish black as were the omentum and the intraperitoneal fat. No other cause of abdominal pain was identified. On histological examination, reddish-purple crystals were identified at frozen section but not in the paraffin sections.

Short-term trial of clofazimine in previously untreated lepromatous leprosy

Forty-five previously untreated lepromatous leprosy patients were allocated randomly to three groups and treated, respectively, with Regimen A, standard dosage of clofazimine (CLO) in multidrug therapy (MDT) regimen; Regimen B, CLO 600 mg once every 4 weeks; and Regimen C, CLO 1200 mg once every 4 weeks. The duration of the trial was 24 weeks. By the end of the trial, although a few patients in each group did not improve at all clinically, the majority of patients showed clinical amelioration but the responses were slow. While the mean morphological index dropped to the baseline after 24 weeks of treatment, the mean bacterial index did not change significantly. About 80% of the patients in each group remained nasal-smear positive at the end of the trial, but the bacterial loads steadily declined. No significant difference has been detected in these parameters among the three groups. The patients tolerated the regimens very well and the side effects were mild. The results of serial mouse foot pad inoculation demonstrated that the positivity rates of multiplication of Mycobacterium leprae in mice and the proportions of viable organisms reduced gradually in all groups. Because the positivity rate at week 24 in Group C did not differ significantly from Group A, but was significantly smaller than that of Group B, we conclude that Regimen C was as active as Regimen A and could be applied for monthly supervised treatment along with rifampin; Regimen B is less effective and should not be used for the treatment of leprosy.