Search PubMed⌕ Search

Biomedical subjects

M Cazzola

Publications and source records attributed to M Cazzola.

At least 37 records · Page 2Linked to original sources
PubMed2002

Formoterol as dry powder oral inhalation compared with salbutamol metered-dose inhaler in acute exacerbations of chronic obstructive pulmonary disease.

BACKGROUND: Acute exacerbations of chronic obstructive pulmonary disease (COPD) are managed with increased doses or frequency of the patient's existing bronchodilator therapy. The use of formoterol in the treatment of mild acute exacerbations of COPD has been suggested; however, a comparison of cumulative doses of formoterol with salbutamol, the gold standard bronchodilator agent for this pathologic condition, is still lacking. OBJECTIVE: The aim of the study was to compare the inhaled beta2-agonists salbutamol (rapid onset, short duration of action) and formoterol (rapid onset, long duration of action), both used as needed in patients attending outpatient clinics because of mild acute exacerbations of COPD (Anthonisen exacerbation type I or II). METHODS: A dose-response curve to formoterol via Turbuhaler or salbutamol via pressurized metered-dose inhaler (pMDI) was constructed. On 2 consecutive days, the patients received, in randomized order, both of the following active dose regimens: A = 12 + 12 + 24 microg formoterol via Turbuhaler (48-microg cumulative metered dose); B = 200 + 200 + 400 microg salbutamol via pMDI (800-microg cumulative metered dose). Dose increments were given at 30-minute intervals, with measurements made 25 minutes after each dose. The maximum forced expiratory volume in 1 second (FEV1) value during the dose-response curve to formoterol or salbutamol was chosen as the primary outcome variable to compare the 2 treatments. Oxygen saturation by pulse oximetry (SpO2) and pulse rate were also measured at each assessment period. Every adverse event, either reported spontaneously by the patients or observed by the investigators, was recorded. RESULTS: Sixteen patients (2 women, 14 men) aged 51 to 77 years (most older than 65 years) participated in the study. Both formoterol and salbutamol induced a large, significant, dose-dependent increase in FEV1, inspiratory capacity (IC), and forced vital ca- pacity (FVC). There was no significant difference between FEV1, IC, and FVC values after 48 microg formoterol and 800 microg salbutamol. There was no significant difference in FEV1 after 24 microg formoterol and 800 microg salbutamol; however, the difference in FEV1 after 24 and 48 microg formoterol was significant. Neither heart rate (mean differences from baseline after 48 microg formoterol, 1.9 beats/min [95% CI, -3.4, 7.2] and 800 microg salbutamol, 3.7 beats/min [95% CI, -1.1, 8.5]) nor SpO2 (mean percentage differences from baseline after 48 microg formoterol, -0.37% [95% CI, -1.22, 0.47] and 800 microg salbutamol, -0.75% [95% CI, -1.73, 0.23]) changed significantly. However, SpO2 decreased below 90% in 2 patients after the highest dose of formoterol and in 1 patient after the highest dose of salbutamol. CONCLUSIONS: In this small, selected group of patients with mild acute exacerbations of COPD, formoterol via Turbuhaler induced a fast bronchodilation that was dose dependent and not significantly different from that caused by salbutamol. Furthermore, formoterol appeared to be as well tolerated as salbutamol.

Administration, Inhalation↗
PubMed2002

Bronchodilating effect of oxitropium bromide in heart disease patients with exacerbations of COPD: double-blind, randomized, controlled study.

Anti-cholinergic agents are considered the bronchodilator therapy of first-choice in the treatment of patients with stable chronic obstructive pulmonary disease (COPD) associated with heart disease since they may be as effective or more effective than inhaled beta2-agonists and, moreover, they do not interact with cardiac beta-adrenoceptors. The aim of our study was to evaluate the bronchodilator activity of oxitropium bromide in outpatients suffering from exacerbations of COPD associated with heart diseases (ischaemic heart disease and/or arrhythmias). We recruited 50 consecutive outpatients (33 males and 17 females, mean age 68.6 years, 15 current smokers and 35 ex-smokers). Each patient performed body plethismography in basal condition and 30 min after inhalation of 200 microg metered dose inhaler (MDI) oxitropium bromide administered by a device (Fluspacer). FEV1, FVC, MMEF25-75, sRaw and tRaw were evaluated. Thirty minutes after 200 microg oxitropium bromide administration, we observed a significant improvement in FEV1 11.6% +/- 1 (mean +/- SEM) (P<0.01); FVC, MMEF25-75 sRaw variation was respectively: 9.2% +/- 0.6, 31.4 +/- 2.9, -19.9 +/- 1.1. Placebo did not significantly change pulmonary function. Our data suggest that oxitropium bromide bronchodilator activity is effective in exacerbations of COPD.

Acute Disease↗
PubMed2002

Addition of an extra dose of salmeterol Diskus to conventional dose of salmeterol Diskus in patients with COPD.

Patients experiencing dyspnoea can request an additional dose of salmeterol during the dose interval for the control of their symptoms, although under treatment with salmeterol. In this study we have explored the effects on respiratory function of an additive dose of salmeterol Diskus in 15 chronic obstructive pulmonary disease (COPD) patients in regular treatment with a conventional dose of 50 microg salmeterol. On two different days, patients inhaled 50 microg Diskus. After 240 min, they inhaled additional 50 microg salmeterol Diskus (salmeterol arm) or placebo Diskus (placebo arm). Lung function was controlled before first drug administration and 0.5, 1, 2, 3, 4, 4.5, 6, 8, 10, and 12 h thereafter. The mean (95% CI) peak increase in FEV1 from baseline was reached after 4 h in the salmeterol arm (0.174 L; 0.144-0204) and after 5 h (0.141 L; 0.115-0.168) inthe placebo arm; after 12 h, the mean (95% Cl) increase in FEV1 from basal values was still 0.149 L (0.119-0.179) in salmeterol arm, but only 0.041 L (0.017-0.064) in placebo arm. The mean (95% CI) FEV1 AUC0-12h for all patients were 2.01 (1.72-2.30) L when salmeterol was added and 1.30 (1.03-1.58) L when placebo was inhaled. The difference (mean; 95% CI) between the FEV1 AUC0-12h of the two arms (0.71 L; 0.47-0.95) was statistically significant (P<0.0001), although the difference (mean; 95% CI) between the FEV1 AUC0-4h of the two treatments (0.08 L; -0.02-0.18) was notstatistically significant (P=0.126). The addition of an extra dose of salmeterol did not significantly increase the heart rate or decrease the SpO2. This study suggests that the addition of an extra dose of salmeterol does not give room for further increase in peak FEV1, but the effect of adding salmeterol to salmeterol is largely additive when considering the duration of action and safe.

Albuterol↗
PubMed2002

Acute effects of higher than customary doses of salmeterol and salbutamol in patients with acute exacerbation of COPD.

Worsening of underlying bronchospasm may be associated with acute exacerbations of chronic obstructive pulmonary disease (COPD). As airway obstruction becomes more severe, the therapeutic option is to add salbutamol, but not salmeterol, as needed to cause rapid relief of bronchospasm. Unfortunately the most effective dosage of beta2-agonists may increase above that recommended during acute exacerbations. In this study, we compared the acute effects of higher than customary doses of salmeterol and salbutamol in 20 patients with acute exacerbation of COPD. A dose-response curve to salmeterol pMDI, 25 microg/puff or salbutamol pMDI, 100 microg/puff, was constructed using 1, 1, and 2 puff' i.e., a total cumulative dose of 100 microg salmeterol or 400 microg salbutamol on 2 consecutive days. After baseline measurements, dose increments were given at 30-min intervals with measurements being made 25 min after each dose. Hear rate (HR) and pulse-oximetry (SpO2) measurements were then taken. Both salmeterol and salbutamol induced a larg and significant (P < 0.05) dose-dependent increase in FEV1 [mean differences from baseline (L) = after 100 microg salmeterol 0.174 (95% CI: 0.112 to 0.237); after 400 microg salbutamol: 0.165 (95% CI: 0.080 to 0.249)], in IC [mean differences from baseline (L) = after 100 microg salmeterol: 0.332 (95% CI: 0.165 to 0.499); after 400 microg salbutamol: 0.281 (95% CI: 0.107 to 0.456)] (Fig. 2), and in FVC mean differences from baseline (L) = after 100 microg salmeterol: 0.224 (95% CI: 0.117 to 0.331); after 400 microg salbutamol: 0.242 (95% CI: 0.090 to 0.395)]. There was no significant difference between the FEV1 values (P=0.418), the ICvalues (P=0.585), and the FVCvalue (P=0.610) after 100 microg salmeterol and 400 microg salbutamol. HR [mean differences from baseline (beats/min) = after 100 microg salmeterol: 3.15 (95% CI: -0.65 to 6.96); after 400 microg salbutamol: 2.30 (95% CI: -0.91 to 5.51)] and SpO2 [mean differences from baseline (%) = after 100 microg salmeterol: -0.20 (95% CI: -1.00 to 0.60); after 400 microg salbutamol: -0.11 (95% CI: -1.00 to 0.79)] did not change significantly from baseline (P > 0.05). These data indicate that salmeterol is effective and safe in the treatment of acute exacerbation of COPD and support its use in this clinical condition.

Acute Disease↗
PubMed2002

Outdoor air pollution, climatic changes and allergic bronchial asthma.

Both the prevalence and severity of respiratory allergic diseases such as bronchial asthma have increased in recent years. Among the factors implicated in this "epidemic" are indoor and outdoor airborne pollutants. Urbanisation with its high levels of vehicle emissions and Westernised lifestyle parallels the increase in respiratory allergy in most industrialised countries, and people who live in urban areas tend to be more affected by the disease than those of rural areas. In atopic subjects, exposure to air pollution increases airway responsiveness to aeroallergens. Pollen is a good model with which to study the interrelationship between air pollution and respiratory allergic diseases. Biological aerosols carrying antigenic proteins, such as pollen grains or plant-derived paucimicronic components, can produce allergic symptoms. By adhering to the surface of these airborne allergenic agents, air pollutants could modify their antigenic properties. Several factors influence this interaction, i.e., type of air pollutant, plant species, nutrient balance, climatic factors, degree of airway sensitisation and hyperresponsiveness of exposed subjects. However, the airway mucosal damage and the impaired mucociliary clearance induced by air pollution may facilitate the penetration and the access of inhaled allergens to the cells of the immune system, and so promote airway sensitisation. As a consequence, an enhanced immunoglobulin E-mediated response to aeroallergens and enhanced airway inflammation favoured by air pollution could account for the increasing prevalence of allergic respiratory diseases in urban areas.

Air Pollutants↗
PubMed2001

Onset of action of single doses of formoterol administered via Turbuhaler in patients with stable COPD.

We studied 16 patients with stable COPD in a double blind, double dummy, placebo-controlled, within patient study to see if formoterol could be used as a rescue drug. We compared the of onset of bronchodilation obtained with formoterol 12 microg (metered dose corresponding to 9 microg delivered dose) and formoterol 24 microg (metered dose corresponding to 18 microg delivered dose), both delivered via Turbuhaler, with that of salbutamol 400 microg and salbutamol 800 microg delivered via pressurized metered-dose inhaler (pMDI). Patients inhaled single doses of placebo, formoterol and salbutamol on five separate days. FEV1 was measured in baseline condition and 3, 6, 9, 12, 15, 18, 21, 24, 30, 40, 50, and 60 min after inhalation of each treatment. We examined two separate criteria for deciding if a response was greater than that expected by a random variation of the measurement: (1) a rise in FEV1 of at least 15% from the baseline value; (2) an absolute increase in FEV1 of at least 200 ml. Formoterol 12 microg (15.2 min; 95% CI 9.5-21.0) and formoterol 24 microg (15.1 min; 95% CI 8.9-21.2) caused a rise in FEV1 of at least 15% from the baseline value almost rapidly as salbutamol 400 microg (13.6 min; 95% CI 7.1-20.1) and salbutamol 800 microg (14.5 min; 95% CI 7.1-21.9). No significant difference (P=0.982) in onset of action was seen between the four active treatments. According to Criterion 2, the mean time to 200 ml increase in FEV1 was 11.1 min (95% CI: 7.0-15.2) after salbutamol 400 microg, 13.0 min (95% CI: 7.9-18.1) after salbutamol 800 microg, 14.7 min (95% CI: 7.1-22.4) after formoterol 12 microg, and 12.7 min (95% CI: 7.4-18.0) after formoterol 24 microg. Again, there was no significant difference (P= 0.817) between the four active treatments. Formoterol Turbuhaler 12 microg and 24 microg caused bronchodilation as rapidly as salbutamol 400 microg and 800 microg given via pMDI.

Acute Disease↗
PubMed2001

Advances in the research and development of chemotherapeutic agents for respiratory tract bacterial infections.

The activity of existing antibiotics is diminishing due to the increasing number of resistant strains and by the increase of infections with naturally resistant microorganisms. New agents are urgently needed to meet this challenge and the molecular strategies adopted for the discovery of these compounds must focus on minimizing the emergence of future resistance to them. Novel compounds can be grouped on the basis of their mechanism of action: inhibitors of nucleic acid synthesis (fluoroquinolones), inhibitors of protein synthesis (ketolides, oxazolidinones, streptogramins, and glycylcyclines), inhibitors of peptidoglycan synthesis (beta-lactams and glycopeptides), and agents interfering with membrane function (cationic peptides, and lipopeptides). Regarding the agents that are already in the research and development pipeline, only the oxazolidinones, the cationic peptides and the lipopeptide antibiotics can be truly considered as structurally novel inhibitors because the other agents are analogues of existing compounds that have been in use for many years.

Anti-Bacterial Agents↗
PubMed2001

Interferon-alpha protects Philadelphia-negative progenitors from exhaustion in chronic myeloid leukemia patients with cytogenetic response.

INTRODUCTION: Normal immature hematopoietic progenitors are relatively well preserved in most patients newly diagnosed with chronic myeloid leukemia, but tend to decline rapidly with time. Such exhaustion could reflect a suppressive effect of the Philadelphia positive clone expansion and/or be induced by Interferon-alpha treatment. MATERIALS AND METHODS: A total of 51 CML patients were classified into three groups. Newly diagnosed untreated patients were group A (n=30). Of the 21 treated individuals with Interferon-alpha, for at least 12 months, 15 showed no cytogenetic response (group B) while six showed persisting major/complete response (group C). Patients belonging to groups A and B were mobilized with chemotherapy plus G-CSF while patients of group C received a short course of G-CSF only. RESULTS: Patients responding to IFN-alpha (group C) showed comparable numbers of bone marrow Ph- long-term culture initiating cells to those of newly diagnosed individuals (group A): 8.5 (<1-65)/10(6) MNC vs 10.5 (<1-30), while non-responders had markedly lower numbers: <1 (<1-5). The amount of Ph- LTC-IC collected was significantly lower in patients of group B 1.8 (0-325)x10(2)/kg than in patients of either group A 31.3 (0-952)x10(2)/kg (P<0.002) or group C 109 (8-259)x10(2)/kg (P<0.01). Interestingly, five patients of group B who had 100% Ph+ metaphases, but Ph- progenitors in their bone marrow, mobilized normal amounts of Ph(-) progenitors. CONCLUSION: These findings suggest that the decline of normal hematopoietic progenitors, currently observed in the majority of CML patients, is not induced by IFN-alpha treatment, but it is likely due to the expanding leukemic clone. They also indicate that normal hematopoietic reservoir is consistently preserved in patients given IFN-alpha early after diagnosis and achieving a stable cytogenetic response.

Adult↗
PubMed2001

The role of outdoor air pollution and climatic changes on the rising trends in respiratory allergy.

Evidence suggests that allergic respiratory diseases such as hay fever and bronchial asthma have become more common world-wide in the last two decades, and the reasons for this increase are still largely unknown. A major responsible factor could be outdoor air pollution, derived from cars and other vehicles. Studies have demonstrated that urbanization and high levels of vehicle emissions and westernized lifestyle is correlated with the increasing frequency of pollen-induced respiratory allergy. People who live in urban areas tend to be more affected by pollen-induced respiratory allergy than those from of rural areas. Pollen allergy has been one of the most frequent models used to study the interrelationship between air pollution and respiratory allergic diseases. Pollen grains or plant-derived paucimicronic components carry allergens that can produce allergic symptoms. They may also interact with air pollution (particulate matter, ozone) in producing these effects. There is evidence that air pollutants may promote airway sensitization by modulating the allergenicity of airborne allergens. Furthermore, airway mucosal damage and impaired mucociliary clearance induced by air pollution may facilitate the access of inhaled allergens to the cells of the immune system. In addition, vegetation reacts with air pollution and environmental conditions and influence the plant allergenicity. Several factors influence this interaction, including type of air pollutants, plant species, nutrient balance, climatic factors, degree of airway sensitization and hyperresponsiveness of exposed subjects.

Air Pollution↗
PubMed2001

Formoterol Turbuhaler for as-needed therapy in patients with mild acute exacerbations of COPD.

Worsening of underlying bronchospasm may be associated with acute exacerbations of chronic obstructive pulmonary disease (COPD). As airway obstruction becomes more severe, the therapeutic option is to add a short-acting inhaled beta2-agonist as needed to cause rapid relief of bronchospasm. Unfortunately however, the most effective dosage may increase above that recommended during acute exacerbations. Formoterol (Oxis) Turbuhaler has a rapid onset of action (within minutes) and demonstrates a maintained effect on a rway function. In this study, we examined the effects of formoterol used as needed in 20 patients with acute exacerbations of COPD. A dose response curve to inhaled formoterol (9 microg per inhalation) or placebo was constructed using three separate inhalations, i.e. a total cumulative dose of 27 microg. Dose increments were given at 20-min intervals, with measurements being made 15 min after each dose. Formoterol, but not placebo, induced a large and significant (P<0.001) dose-dependent increase in forced expiratory volume in 1 sec (FEV1) [mean differences from baseline = 0.1311 after 9 microg formoterol (95% CI: 0.096-0.167)] 0.1811 after 18 microg formoterol (95% CI: 0.140-0.2221) and 0.2081 after 27 microg formoterol (95% CI: 0.153-0.2631). However, 27 microg formoterol did not induce further benefit [0.0271 (95% CI: -0.008-0.0621); P=0.121] when compared wth 18 microg formoterol. Results of this study suggest the use of higher than customary dose of formoterol for as-needed therapy to provide rapid relief of bronchospasm in patients suffering from acute exacerbations of partially reversible COPD.

Acute Disease↗
PubMed2001

Comparison of the bronchodilating effect of salmeterol and zafirlukast in combination with that of their use as single treatments in asthma and chronic obstructive pulmonary disease.

BACKGROUND: It has been suggested that the effect of a beta2-agonist is additive with that of a cysteinyl leukotriene 1 receptor antagonist. OBJECTIVES: The present study was designed to answer the question of whether combined administration of inhaled salmeterol and oral zafirlukast at the standard doses would result in greater bronchodilation in patients with chronic airway obstruction than the use of either drug alone. METHODS: The study was performed using a double-blind, double-dummy, crossover, randomised design, and was conducted on 4 non-consecutive days. Sixteen patients with moderate to severe chronic obstructive pulmonary disease (COPD) and 10 non-smoker asthmatic patients received 40 mg of oral zafirlukast, 50 microg of inhaled salmeterol, 50 microg of inhaled salmeterol plus 40 mg of oral zafirlukast of placebo. Lung function was assessed before drug administration and 30, 60, 120, 180 and 240 min thereafter. At the end of the 4-hour period, each patient received 400 microg of inhaled salbutamol and spirometric testing was performed 30 min later. RESULTS: In both asthmatic and COPD patients, the overall effect of salmeterol and zafirlukast on the forced expiratory volume in 1 s (FEV1) was considered extremely significant (p < 0.0001), with a maximum bronchodilation above baseline after 180 min (20.7 and 11.0%, respectively) in asthmatics and after 2 h (21.7 and 11.2%, respectively) in COPD subjects. Zafirlukast did not produce any further significant acute bronchodilation in addition to that achieved with salmeterol alone in either asthmatic or COPD patients. Nevertheless, 7 out of 16 COPD patients and 7 out of 10 asthmatic patients had a further improvement after the combination of salmeterol and zafirlukast. The mean difference in pre- and post-salbutamol FEV1 values in both asthmatic and COPD patients after zafirlukast was significant (p < 0.05), but that after salmeterol and the combination of the two drugs was not significant (p > 0.05). The difference between placebo and zafirlukast was not significant following inhaled salbutamol given 4 h after each treatment. CONCLUSIONS: Both salmeterol and zafirlukast induced a significant increase in FEV1, although salmeterol elicited a greater improvement in both asthmatic and COPD patients. Apparently, zafirlukast at the clinically recommended dose did not produce any further significant acute bronchodilation in addition to that achieved with salmeterol alone, either in asthma or COPD. In any case, evaluation of the effect of the combination over a 12-hour period is mandatory.

Adrenergic beta-Agonists↗
PubMed2001

Pulmonary disposition of lomefloxacin in patients with acute exacerbation of chronic obstructive pulmonary disease. A multiple-dose study.

In this study we have measured the concentrations of lomefloxacin at steady state in serum and in the intrapulmonary region at specified intervals for 24 h following administration of the last dose of drug in patients suffering from acute exacerbation of chronic obstructive pulmonary disease (COPD). Twenty subjects were enrolled. They received lomefloxacin 400 mg orally once-daily for 5 consecutive days. All patients were divided into five groups, with 4 subjects in each group, according to sampling times (2, 4, 8, 12, and 24 h after the last dose). At bronchoscopy, bronchial biopsies and bronchoalveolar lavage (BAL) were performed. At 12 h after the last dose, serum concentration of lomefloxacin was >1.0 microg/mL and at 24 h it was still detectable, but, at all times, the concentrations in bronchial secretion, bronchial mucosa, and epithelial lining fluid (ELF) were greater than the concentrations in serum [bronchial secretions (pg/mL) = 2.5+/-1.2; 2.2+/-1.0: 2.0+/-1.1; 1.8+/-1.1; 0.6+/-0.3. bronchial mucosa (microg/g) = 5.9+/-2.1; 6.2+/-1.8; 2.6+/-2.2; 1.9+/-1.5; 1.0+/-0.9. ELF (microg/mL) = 6.9+/-2.8; 5.9+/-2.6; 3.1+/-1.9; 2.2+/-1.0; 0.8+/-1.3. serum (microg/mL) = 3.2+/-1.4; 2.8+/-0.9: 2.1+/-1.5; 1.2+/-1.1; 0.4+/-0.81. We must stress that we observed a large inter-individual variability in concentrations. Our data show that lomefloxacin once-daily induces high and sustained concentrations in the various potential sites of pulmonary infection and clearly indicate that the pharmacokinetic behavior of this fluoroquinolone permits once-daily administration in patients with acute exacerbations of COPD.

Administration, Oral↗
PubMed2001

Mechanisms and characteristics of airway sensitization to indoor allergens.

The increasing prevalence of allergic respiratory diseases, and particularly of bronchial asthma, has been linked to changes induced by human activities in outdoor and indoor environments. People living in industrialized countries spend most of their time indoors: in private homes, offices and means of transport. Indoor environments are not a refuge from outdoor air pollution. Modern systems for energy saving such as insulated windows and doors reduce the indoor natural ventilation and consequently increase the rate of indoor humidity. These conditions may determine an increase in the level of indoor pollutants (tobacco smoke, gases produced by cooling processes etc.) and of allergens derived from mites, domestic animals and cockroaches. Upholstered furniture, wall-to-wall carpets, central heating systems and/or humidifiers may also contribute to the growth of mite populations. The increasing levels of exposure to pollutants and allergens in indoor environments represents a risk factor for the development of airway sensitization, especially if these materials are inhaled early in life. The major cat allergen Fel d 1 is considered an ubiquitous allergen, since it has been found in many indoor environments where a cat has never been kept. The clothing of cat owners seems to help spread Fel d 1 in cat-free environments. Sensitization to cockroach allergens is very common in patients living in urban areas where unhygenic conditions may favour the growth of cockroach populations. Monitoring of the levels of allergens and strategies of allergen and pollutant avoidance in indoor environments are the main ways to reduce the prevalence of respiratory allergies induced by these materials.

Air Pollution, Indoor↗
PubMed2000

Familial-skewed X-chromosome inactivation as a predisposing factor for late-onset X-linked sideroblastic anemia in carrier females.

X-linked sideroblastic anemia (XLSA) is caused by mutations in the erythroid-specific 5-aminolevulinic acid synthase (ALAS2) gene. An elderly woman who presented with an acquired sideroblastic anemia is studied. Molecular analysis revealed that she was heterozygous for a missense mutation in the ALAS2 gene, but she expressed only the mutated gene in reticulocytes. Her 2 daughters and a granddaughter were heterozygous for this mutation, had normal hemoglobin levels, and expressed the normal ALAS2 gene in reticulocytes. A grandson with a previous diagnosis of thalassemia intermedia was found to be hemizygous for the ALAS2 mutation. Treatment with pyridoxine completely corrected the anemia both in the proband and her grandson. All women who were analyzed in this family showed skewed X-chromosome inactivation in leukocytes, which indicated a hereditary condition associated with unbalanced lyonization. Because the preferentially active X chromosome carried the mutant ALAS2 allele, acquired skewing in the elderly likely worsened the genetic condition and abolished the normal ALAS2 allele expression in the proband. (Blood. 2000;96:4363-4365)

5-Aminolevulinate Synthetase↗