Acetyl-l-carnitine and nucleoside reverse transcriptase inhibitor-associated neuropathy in HIV infection.

OBJECTIVES: Antiretroviral toxic neuropathy (ATN) is associated with dideoxynucleoside reverse transcriptase inhibitor use in patients infected with HIV, possibly as a result of mitochondrial toxicity. Acetyl-l-carnitine (ALC) has been linked to symptomatic improvement in ATN. We present an open-label single-arm pilot study to evaluate changes in intra-epidermal nerve fibre (IENF) density and mitochondrial DNA (mtDNA) copies/cell among subjects treated with 3000 mg ALC daily. METHODS: Punch skin biopsies were examined at baseline and after 24 weeks of therapy. Participants reported neuropathic symptoms using the Gracely Pain Intensity Score. Neurological examinations were completed. RESULTS: Twenty-one subjects completed the study. ALC was generally well tolerated. The IENF density did not change in cases completing 24 weeks of ALC therapy, with median (90% confidence interval) IENF changes of -1.70 (-3.50, infinity) (P=0.98) and 2.15 (-0.10, infinity) (P=0.11) for the distal leg and proximal thigh, respectively. Fat mtDNA copies/cell did not change with therapy. Improvements in neuropathic pain (P<0.01), paresthesias (P=0.01), and symptoms of numbness (P<0.01) were noted. Similarly, improvement was noted on the Gracely Pain Intensity Score. CONCLUSIONS: ALC therapy coincided with improvements in subjective measures of pain in this open-label single-arm study. However, changes were not observed in objective measures of IENF density or mtDNA levels, providing little objective support for use of ALC in this setting.

Correlates of epidermal nerve fiber densities in HIV-associated distal sensory polyneuropathy.

OBJECTIVE: To demonstrate the relationship between epidermal nerve fiber density (ENFD) in the leg and the phenotype of HIV-associated distal sensory polyneuropathy (HIV-DSP) in a multicenter prospective study (ACTG A5117). METHODS: A total of 101 HIV-infected adults, with CD4 cell count <300 cells/mm(3) and who had received antiretroviral therapy (ART) for at least 15 consecutive weeks, underwent standardized clinical and electrophysiologic assessment. All 101 subjects were biopsied at the distal leg (DL) and 99 at the proximal thigh (PT) at baseline. ENFD was assessed by skin biopsy using PGP9.5 immunostaining. Associations of ENFD with demographics, ART treatment, Total Neuropathy Score (TNS), sural sensory nerve action potential (SNAP) amplitude and conduction velocity, quantitative sensory testing (QST) measures, and neuropathic pain were explored. RESULTS: ENFD at the DL site correlated with neuropathy severity as gauged by TNS (p < 0.01), the level of neuropathic pain quantified by the Gracely Pain Scale (GPS) (p = 0.01) and Visual Analogue Scale (VAS) (p = 0.01), sural SNAP amplitude (p < 0.01), and toe cooling (p < 0.01) and vibration (p = 0.02) detection thresholds. ENFD did not correlate with neurotoxic ART exposure, CD4 cell count, or plasma HIV-1 viral load. CONCLUSIONS: In subjects with advanced HIV-1 infection, epidermal nerve fiber density (ENFD) assessment correlates with the clinical and electrophysiologic severity of distal sensory polyneuropathy (DSP). ENFD did not correlate with previously established risk factors for HIV-DSP, including CD4 cell count, plasma HIV-1 viral load, and neurotoxic antiretroviral therapy exposure.

Antiretroviral use and other risks for HIV-associated neuropathies in an international cohort.

OBJECTIVE: To explore the association between specific nucleoside reverse transcriptase inhibitors and sensory neuropathies (SNs) and define the modifying roles of hepatitis C (HCV), vitamin B12 deficiency, and impaired glucose tolerance. METHODS: The authors conducted a prospective cohort study of 147 HIV-infected adults at two sites chosen to emphasize demographic differences. Standardized assessments included detailed antiretroviral histories, neurologic examinations, skin biopsies for epidermal nerve quantitation, and quantitative sensory testing. RESULTS: There were significant differences between subjects at Johns Hopkins University (JHU) and Monash University (MU) in gender, race, HIV transmission route, and HCV seroprevalence. Symptomatic SN was present in 49% at JHU and 55% at MU (chi2 = 4.02, p = 0.134) and was significantly more common in those at least age 40 than younger patients (odds ratio [OR] = 2.87, 95% CI = 1.27, 6.49). After adjusting for site, age, and CD4 cell count, exposure to didanosine (ddI) or stavudine (d4T) was associated with an significantly increased likelihood of symptomatic SN (ddI: OR = 3.21, 95% CI: 1.56, 6.60; d4T: OR = 7.66, 95% CI: 2.89, 20.33). Plasma HIV RNA, lactate, and HCV were not associated with SN. Quantitative vibratory testing identified neuropathy with a positive predictive value of 76% and epidermal nerve fiber densities 59%. CONCLUSIONS: Exposure to stavudine and didanosine was significantly associated with a heightened risk for symptomatic sensory neuropathy. Reduced vibration thresholds and epidermal nerve fiber densities had the highest diagnostic efficiency of the laboratory indicators of neuropathy examined, but were relatively insensitive in isolation.

Expression of protein gene product 9.5 in lepromatous eyes showing ciliary body nerve damage and a "dying back" phenomenon in the posterior ciliary nerves.

BACKGROUND/AIM: Peripheral nerve destruction is the hallmark of leprosy. Ocular complications form a substantial part of the clinical manifestations but histopathology of nerve destruction within ocular structures has not been shown satisfactorily. The role of protein gene product (PGP) 9.5 in identifying nerve destruction in the ciliary body and posterior ciliary nerves of lepromatous eyes is shown. METHODS: Serial sections from two lepromatous eyes and two non-lepromatous eyes were stained with PGP 9.5. Histopathological comparison was done on the expression of the PGP 9.5 stain in nerves within the ciliary body, posterior ciliary nerves adjacent to the optic nerve, and nerves tracking through the sclera. RESULTS: In non-lepromatous eyes, PGP 9.5 was expressed in nerves within the ciliary body, the nerves within the sclera, and posterior ciliary nerves adjacent to the optic nerve. In lepromatous eyes no PGP 9.5 was expressed, signifying nerve destruction. CONCLUSIONS: Nerve destruction in lepromatous eyes has been confirmed histopathologically by the absence of or patchy staining with PGP 9.5. Nerve destruction in the ciliary body can extend to the posterior ciliary nerves by an ascending axonopathy. This "dying back" phenomenon is akin to the "glove and stocking" anaesthesia found in lepromatous leprosy.

Are viable Mycobacterium leprae present in lepromatous patients after completion of 12 months' and 24 months' multi-drug therapy?

A study was carried out to determine whether or not viable bacilli persist in MB patients treated with 12-month and 24-month multidrug therapy (MDT). In the first group, 60 untreated lepromatous patients who had an initial average bacterial index (BI) of 3+ or more were enrolled. At the completion of 12 months of MDT, skin biopsies were obtained and M. leprae concentrate was inoculated into the footpads of five thymectomized and irradiated (T900r) mice. Rees technique was used for the mouse footpad (MFP) experiment. Harvesting was done it the 6th, 9th and 12th months. Out of the 60 biopsies inoculated into mouse footpads to check the viability of bacilli, 2 skin biopsies (3.3%) showed significant growth and 10 (16%) showed equivocal growth. 27 patients also had nerve biopsies tested for growth in MFP studies. None of the inoculated nerve biopsies showed significant multiplication in the MFP experiments. However, 4 biopsies (14%) showed equivocal growth. In the second group, 20 patients had skin biopsies and 10 had nerve biopsies done at the end of 24 doses of MDT in order to test the viability of bacilli; none of the skin or nerve biopsies from these patients showed any growth. This study showed that M. leprae present in the tissues after 24 doses of MDT are not viable and the drug schedule of 24 doses is adequate to treat leprosy patients, irrespective of their BI. However, a small (3.3%) percentage of the patients with a high BI harbour viable bacteria in the skin after 12 doses of treatment. Since a large majority of the patients (38 patients) who had a high initial BI responded well to the treatment, it is important to find out the reason for the lack of response in two patients. One of the reasons may be the presence of drug-resistant strains. It is important to follow up on these patients for a longer duration to ascertain whether or not they would relapse.

Drug resistant-Mycobacterium leprae--results of mouse footpad studies from a laboratory in south India.

Out of 265 biopsies of leprosy patients received at the Experimental Pathology Laboratory of Schieffelin Leprosy Research and Training Centre from 1987 to 1997 for evaluating resistant strains of M. leprae, using the mouse footpad technique, 49 showed resistant strains of M leprae to varying concentrations of dapsone, rifampicin and clofazimine. 23 (47%) of these were from a control area. With 369 skin-smear positive multibacillary (MB) patients as the risk group (denominator), 23 (6.23%) were resistant to one or more drugs. 18 (4.88%) had dapsone resistance, 5 (1.36%) were resistant to rifampicin and 9 (2.44%) had resistance to low concentrations of clofazimine (0.0001%). Out of the 23 biopsies with drug resistance from the control area, primary dapsone resistance was seen in 7 (30%) biopsies and secondary dapsone resistance in 11 (48%). Primary rifampicin resistance was seen in 4 (17.4%) patients, secondary rifampicin resistance in 1 (4.35%) and primary clofazimine resistance in 7 (30%). 3 (13%) of the strains showed secondary clofazimine resistance. One biopsy had resistant strains to all the three drugs. In a control area where properly supervised effective multidrug therapy (MDT) was regularly administered over the years, the emergence of drug resistance is negligible. It may not be the case if the content, duration and regularity of the drug regimen were not satisfactory. Aware of the possible shortcomings in mass administration of MDT, it is emphasized that mouse footpad studies on drug resistance should be made available at least in endemic areas where the incidence of the disease has not changed despite good MDT coverage in order to monitor the emergence of drug resistance. Research into molecular biological identification of drug resistant-M.leprae should be intensified. These steps would help to institute timely measures to check the spread of any drug-resistant organisms in the community.

Drug resistant-Mycobacterium leprae--results of mouse footpad studies from a laboratory in south India

Out of 265 biopsies of leprosy patients received at the Experimental Pathology Laboratory of Schieffelin Leprosy Research and Training Centre from 1987 to 1997 for evaluating resistant strains of M. leprae, using the mouse footpad technique, 49 showed resistant strains of M leprae to varying concentrations of dapsone, rifampicin and clofazimine. 23 (47%) of these were from a control area. With 369 skin-smear positive multibacillary (MB) patients as the risk group (denominator), 23 (6.23%) were resistant to one or more drugs. 18 (4.88%) had dapsone resistance, 5 (1.36%) were resistant to rifampicin and 9 (2.44%) had resistance to low concentrations of clofazimine (0.0001%). Out of the 23 biopsies with drug resistance from the control area, primary dapsone resistance was seen in 7 (30%) biopsies and secondary dapsone resistance in 11 (48%). Primary rifampicin resistance was seen in 4 (17.4%) patients, secondary rifampicin resistance in 1 (4.35%) and primary clofazimine resistance in 7 (30%). 3 (13%) of the strains showed secondary clofazimine resistance. One biopsy had resistant strains to all the three drugs. In a control area where properly supervised effective multidrug therapy (MDT) was regularly administered over the years, the emergence of drug resistance is negligible. It may not be the case if the content, duration and regularity of the drug regimen were not satisfactory. Aware of the possible shortcomings in mass administration of MDT, it is emphasized that mouse footpad studies on drug resistance should be made available at least in endemic areas where the incidence of the disease has not changed despite good MDT coverage in order to monitor the emergence of drug resistance. Research into molecular biological identification of drug resistant-M.leprae should be intensified. These steps would help to institute timely measures to check the spread of any drug-resistant organisms in the community.

Epithelioid granuloma in the iris of a lepromatous leprosy patient; an unusual finding.

This case report depicts a case of histopathologically confirmed polar lepromatous (LL) leprosy with a bacterial index of 4+. He experienced recurrent episodes of erythema nodosum leprosum (ENL) in the first 5 years after diagnosis. Skin smears became negative after 6 years of dapsone monotherapy and have remained negative since that time. At 23 years after diagnosis, the patient had developed cataracts and underwent intracapsular cataract extractions with broad-based iridectomies. In one of the iris specimens, histopathologic examination revealed a focal granuloma composed of epithelioid cells. Subsequently a lepromin skin test showed a positive Mitsuda reaction with a borderline tuberculoid histopathology. This clearly illustrates the immunological upgrading of a polar lepromatous patient, perceived first in the iris tissue.

Pathology of a lepromatous eye.

Histopathological examination of an enucleated eye from a lepromatous leprosy patient showed the cornea, ciliary body, and part of the choroid to be infiltrated by macrophages filled with Mycobacterium leprae. The walls of blood vessels in the sclera, ciliary body and the anterior choroid demonstrated the presence of M. leprae, giving credence to the blood-borne entry of M. leprae into the eye. Unlike the eyes of experimental animals infected with M. leprae, histopathological study of this eye from a lepromatous leprosy patient demonstrated that M. leprae, although demonstrable in the anterior choroid, could not be found in the posterior parts of the eye, substantiating the claim that leprosy does not affect the posterior parts of the eye directly.

Lepromatous lymphadenopathy and concomitant tuberculous axillary lymphadenitis with sinus. A case report.

A 25-year-old male patient with florid lepromatous leprosy presented with right axillary lymphadenopathy and a discharging sinus. He also had scabies with chronic right otitis media. Histopathological examination of the lymph node revealed lepromatous lymphadenitis coexisting with tuberculosis. This unusual combination of two different clinical entities is recorded in this case report.

Nasal mucosa and skin of smear-positive leprosy patients after 24 months of fixed duration MDT: histopathological and microbiological study.

The skin and nasal mucosa of 10 lepromatous leprosy patients who had completed 24 doses of fixed duration multidrug therapy (MDT) but who continued to be skin-smear positive for acid-fast bacilli (AFB) were examined histopathologically. The nasal mucosa showed granuloma fractions that exceeded those seen in the skin specimens, signifying that activity in this region subsides much more gradually than the activity in the skin. Mouse foot pad studies done using T900r mice with an inoculum from the nasal mucosa biopsy specimens of these patients did not demonstrate any growth of Mycobacterium leprae, indicating that these bacilli were not viable. A skin specimen from one patient grew significant amounts of bacteria in the T900r mouse foot pad. These results show that 2 years of treatment with MDT would prevent dissemination of M. leprae from the nasal mucosa and, therefore, should preclude further transmission of the disease. It also indicates that viable bacteria might persist in the skin of patients, especially those with an initial bacterial index of > or = 4+ who have completed 24 doses of regular MDT. Therefore, a more cautious approach to administering only 12 doses of MDT to highly positive multibacillary patients is suggested.

Histopathological activity in paucibacillary leprosy patients after ROM therapy.

Histopathological activity was assessed in the skin tissue of 13 skin-smear negative, borderline tuberculoid leprosy patients after administration of a single dose of ROM (rifampin 600 mg, ofloxacin 400 mg and minocycline 100 mg) therapy. Biopsies taken just before therapy showed Mycobacterium leprae to be present in eight cases. After 6 months, only three showed granulomatous lesions and others showed only resolving or inactive lesions. Acid-fast bacilli (AFB) persisted in the nerves of three cases. At the end of 12 months, granulomas persisted in 2 out of 13 (15%) patients. No bacilli, however, were detected in any of them at the end of 12 months. This study demonstrated that 12 months after a single dose of ROM granuloma cleared in 85% of the patients and AFB were absent in all of them.

Clinical and histopathological activity in paucibacillary leprosy patients after fixed-duration multidrug therapy.

In 37 clinically-diagnosed borderline-tuberculoid (BT) leprosy patients skin biopsies were done prior to starting multidrug therapy (MDT) and at the end of 6 months therapy. Clinical and histopathological activity, graded as active, resolving and inactive, were studied at the end of 6 months of MDT. Of the 37 clinically-diagnosed BT patients 24 could be confirmed by histopathology as having BT leprosy, while the other 13 biopsies showed features of indeterminate (I) leprosy. After 6 months of MDT, out of the 24 histopathologically-confirmed BT patients, 4 (17%) showed clinical activity and 8 (33%) showed histopathological activity. Of the 13 histopathologically-diagnosed indeterminate cases all were clinically inactive but histological activity persisted in 3 cases (23%). Out of the 37 clinically-diagnosed BT patients 3 showed both clinical and histopathological activity at the end of MDT. This study emphasizes the importance of performing histopathological examinations on leprosy patients undergoing research studies for the confirmation of diagnosis and for proper classification of the disease. The histopathological activity that outlasts the MDT may be due to the bacillary fragments that persist but clinical activity coupled with histopathological activity seen in 3 patients at the end of 6 months may foreshadow a relapse and these patients and others like them need to be followed up for longer durations.