Improvement of pure sensory mononeuritis multiplex and IgG1 deficiency with sitagliptin plus Vitamin D3.

INTRODUCTION: Mononeuritis multiplex (MM) is an unusual form of peripheral neuropathy involving at least two noncontiguous peripheral nerve trunks. The pure sensory form of MM occurs rarely. Immunoglobulin (Ig)G subclass deficiency is a clinically and genetically heterogeneous disorder. Up to 50% of adults with selective subnormal IgG1 levels or selective IgG1 deficiency have a concomitant autoimmune disorder. Herein, we report the case of a patient with MM and selective IgG1 deficiency who showed remarkable clinical improvement after 2-year combination therapy with the DPP-4 inhibitor sitagliptin plus vitamin D3. CASE REPORT: A 49-year-old man developed numbness in right hand and forearm. After 6 months, the patient developed left forefoot numbness. Approximately 8 years later, the patient started to develop numbness also in the right forefoot, along with symptoms of evening fatigue and occasional orthostatic hypotension. The patient also reported recurrent candidiasis in glans and intergluteal areas since adolescence. Electromyoneurography of lower and upper limbs revealed the presence of multiple mononeuropathies. Protein electrophoresis showed hypogammaglobulinemia and low serum IgG1 levels. Sural nerve biopsy showed the presence of perineuritis. The patient was diagnosed with MM due to perineuritis probably secondary to IgG1 deficiency. We, then, proposed combination therapy with sitagliptin and vitamin D3 in the attempt to achieve immunomodulation. At the last follow-up visit (2 years), the patient showed persistent clinical improvement, increase in IgG1 levels and normalization of protein electrophoresis. CONCLUSIONS: To the best of our knowledge, this is the first case showing a remarkable clinical improvement of MM and selective IgG1 deficiency achieved through a combination therapy with sitagliptin and vitamin D3.

Intravenous immunoglobulin for preventing infection in preterm and/or low birth weight infants.

BACKGROUND: Nosocomial infections continue to be a significant cause of morbidity and mortality among preterm and/or low birth weight (LBW) infants. Preterm infants are deficient in immunoglobulin G (IgG); therefore, administration of intravenous immunoglobulin (IVIG) may have the potential of preventing or altering the course of nosocomial infections. OBJECTIVES: To use systematic review/meta-analytical techniques to determine whether IVIG administration (compared with placebo or no intervention) to preterm (< 37 weeks' postmenstrual age (PMA) at birth) or LBW (< 2500 g birth weight) infants or both is effective/safe in preventing nosocomial infection. SEARCH METHODS: For this update, MEDLINE, EMBASE, CINAHL, The Cochrane Library, Controlled Trials, ClinicalTrials.gov and PAS Abstracts2view were searched in May 2013. SELECTION CRITERIA: We selected randomised controlled trials (RCTs) in which a group of participants to whom IVIG was given was compared with a control group that received a placebo or no intervention for preterm (< 37 weeks' gestational age) and/or LBW (< 2500 g) infants. Studies that were primarily designed to assess the effect of IVIG on humoral immune markers were excluded, as were studies in which the follow-up period was one week or less. DATA COLLECTION AND ANALYSIS: Data collection and analysis was performed in accordance with the methods of the Cochrane Neonatal Review Group. MAIN RESULTS: Nineteen studies enrolling approximately 5000 preterm and/or LBW infants met inclusion criteria. No new trials were identified in May 2013. When all studies were combined, a significant reduction in sepsis was noted (typical risk ratio (RR) 0.85, 95% confidence interval (CI) 0.74 to 0.98; typical risk difference (RD) -0.03, 95% CI 0.00 to -0.05; number needed to treat for an additional beneficial outcome (NNTB) 33, 95% CI 20 to infinity), and moderate between-study heterogeneity was reported (I2 54% for RR, 55% for RD). A significant reduction of one or more episodes was found for any serious infection when all studies were combined (typical RR 0.82, 95% CI 0.74 to 0.92; typical RD -0.04, 95% CI -0.02 to -0.06; NNTB 25, 95% CI 17 to 50), and moderate between-study heterogeneity was observed (I2 50% for RR, 62% for RD). No statistically significant differences in mortality from all causes were noted (typical RR 0.89, 95% CI 0.75 to 1.05; typical RD -0.01, 95% CI -0.03 to 0.01), and no heterogeneity for RR (I2 = 21%) or low heterogeneity for RD was documented (I2 = 28%). No statistically significant difference was seen in mortality from infection; in incidence of necrotizing enterocolitis (NEC), bronchopulmonary dysplasia (BPD) or intraventricular haemorrhage (IVH) or in length of hospital stay. No major adverse effects of IVIG were reported in any of these studies. AUTHORS' CONCLUSIONS: IVIG administration results in a 3% reduction in sepsis and a 4% reduction in one or more episodes of any serious infection but is not associated with reductions in other clinically important outcomes, including mortality. Prophylactic use of IVIG is not associated with any short-term serious side effects. The decision to use prophylactic IVIG will depend on the costs and the values assigned to the clinical outcomes. There is no justification for conducting additional RCTs to test the efficacy of previously studied IVIG preparations in reducing nosocomial infections in preterm and/or LBW infants.

Clinical and Immunological Features of 78 Adult Patients with Primary Selective IgG Subclass Deficiencies.

The purpose of this study is to describe both clinical and immunological features in large cohort of adult patients with IgG subclass deficiency, and response to immunoglobulin therapy. This is a retrospective study of data obtained from electronic medical records and paper charts of 78 patients with IgG subclass deficiency seen and followed at our immunology clinics from 2010 to 2016. Both isolated selective IgG subclass deficiency as well as combined (two) subclass deficiencies were observed. IgG3 subclass deficiency, isolated and in combination with other IgG subclass deficiency, is the most frequent of IgG subclass deficiency. A majority of patients presented with upper and lower respiratory tract infections, especially chronic sinusitis. Both allergic and autoimmune manifestations are common; however, there is no subclass preference. The proportions and absolute numbers of CD3+ T cells, CD4+ T and CD8+ T cells, CD19+ B cells, and CD3-CD16+CD56+ NK cells were normal in the majority of patients in all IgG subclass deficiencies. Total serum IgG levels did not correlate with IgG subclass levels across all IgG subclass deficiencies. Anti-pneumococcal polysaccharide antibody responses were impaired in 56% of patients. IgG3 subclass deficiency is the most common IgG subclass deficiency, and anti-polysaccharide antibody responses are distributed among IgG subclasses with modest preference in IgG2 subclass. The majority of patients treated with immunoglobulin responded by reduction in frequency of infections and requirement of antibiotics.

Lifelong immunoglobulin replacement is not always necessary: A case description of a patient with recurrent infections and hypogammaglobulinemia.

Humoral immunodeficiency with accompanying infections is an indication for human immunoglobulin replacement therapy. Whether treatment will be lifelong or necessary only temporarily depends on the nature of deficiency: primary (persistent) or secondary (persistent or transient). It is not always easy to distinguish between primary and secondary immunodeficiency, especially in adults. The article presents a case of a 39-year-old patient with anamnesis and medical tests results that suggested primary humoral immunodeficiency. The deficiency was diagnosed for the first time at the age of 38, when the patient was pregnant. The patient was qualified for immunoglobulin G replacement therapy. Clinical improvement was achieved. After the end of pregnancy, systematic improvement in immunological parameters was observed, suggesting the resolution of immunodeficiency. A decision was made to discontinue immunoglobulin replacement. Due to the ability to respond to vaccine, confirmed during diagnosis, preventive vaccines were recommended. There was no recurrence of serious infections. The clinical course finally enabled a diagnosis of secondary immunodeficiency. The presented case shows the importance of an active approach to the diagnostic and therapeutic process, constant assessment of clinical course, monitoring of IgG concentrations, and the awareness that in the situation when we do not have a genetic confirmation of the disease, the diagnosis may change.

Gamma globulin replacement therapy in uncontrolled, severe asthma associated with humoral immunodeficiency: A series of five case reports.

We report on five adult cases of the rare association of asthma with humoral immunodeficiency (huID). All patients had uncontrolled asthma related to recurrent respiratory infections. Asthma was diagnosed according to the Global Initiative for Asthma (GINA) guidelines, and bronchiectasis was ruled out by a CT chest scan. Two men (aged 28 and 60) presented with pollen allergies, chronic rhinosinusitis, and IgG deficiency (7.8 and 7.6 g/L, respectively). Both patients underwent surgery for nasal polyposis but relapsed with acute sinusitis and severe asthma exacerbations requiring treatment with oral corticosteroids and antibiotics. The immunoglobulin replacement therapy (IRT) partially relieved the asthma by reducing the number of exacerbations. A 55-year-old woman presented with nonallergic, corticosteroid-dependent asthma (20 mg/day prednisone) and IgG deficiency (5.72 g/L). IRT improved asthma control (fall in the Asthma Control Questionnaire (ACQ)-7 score from 3.5 to 1.7) and enabled withdrawal of the corticosteroids. In a 47-year-old woman with an IgG2 subclass deficiency (1.9 g/L) and asthma, IRT increased the degree of asthma control (fall in the ACQ-7 score from 2.8 to 1.1). A 75-year-old woman presented with corticosteroid-dependent asthma (40 mg/day prednisone), IgM and IgG deficiencies (0.28 g/L and 5.36 g/L, respectively), and recurrent respiratory, skin and urinary infections. Again, IRT improved asthma control (fall in the ACQ-7 score from 2.5 to 1.2), reduced the number of hospitalizations for asthma exacerbations, and enabled a 10-mg reduction in the daily dose of prednisone. These observations suggest that IRT may improve disease control in some patients with asthma and associated huID.

IgG subclass deficiencies in children: Facts and fiction.

The chance to analyse the four IgG subclasses arose with the publication of Terry and Fahey1 . Since then, a lot of new information on the role of subclasses and their deficiency states in humans has been obtained. This review tries to analyse critically our current knowledge of subclass deficiencies in children.

Intravenous Immunoglobulin-Induced Pulmonary Embolism: It Is Time to Act!

Pulmonary embolism (PE) is a common clinical problem affecting 600,000 patients per year in the United States. Although the diagnosis can be easily confirmed by imaging techniques, such as computed tomographic angiography of the chest, the identification of underlying mechanism leading to PE is important for appropriate duration of anticoagulation, and prevention of subsequent episodes. The differential diagnosis of underlying mechanism is broad and must include careful review of medication history. Drug-related thromboembolic disease can be easily missed and may have catastrophic consequences. The identification of the culprit drug is important for prevention of subsequent episodes and choosing appropriate duration of anticoagulation. We report a case of a middle-aged man who developed PE after administration of intravenous immunoglobulin.

Overcoming recurrent spontaneous abortions in women suffering from IgG subclass deficiency: high efficiency of low dose intravenous immunoglobulins treatment.

PROBLEM: It's well known that iv. immunoglobulins may be useful to overcome habitual abortions, but the mechanisms at the base of a successful outcome and the likelihoods are still unknown. METHOD OF STUDY: In one hundred and sixty women with habitual abortions and one hundred and sixty healthy mothers, we evaluated blood IgG subclasses; among the patients, sixteen merely showed IgG subclass deficiency, after leaving out any autoimmunity and/or coagulation disorders. All the patients (100%) showed IgG3, twelve (75%) IgG1, eight (50%) IgG4 and six (37,5%) IgG2 deficiency; healthy control people's IgG subclasses fell in normal range in 156 women, but just four women showed IgG2 and IgG4 deficiency with neither immune deficiency's clinical marks nor increased vulnerability to infections. All the patients were treated with whole immunoglobulins iv. infusion (200 mg/kg/monthly) all over the pregnancy. RESULTS: The successful pregnancy rate is very high (>90%): 100% out of women showing IgG1 (12/12), 87,5% of IgG3 (14/16), 75% of IgG4 (6/8) and 66% of IgG2 deficiency (4/6) had successful pregnancies. The Odd's Ratio between IgG subclass deficiency and recurrent abortions is 4,33 with confidence interval of 95%; chi square value is 7.68 (p<0.025). CONCLUSIONS: Low dose immunoglobulin infusion is the only effective way to reach successful pregnancy, despite previous habitual abortions in patients suffering from IgG subclass deficiency without autoimmunity and/or coagulation disorders, likely restoring idiotype-antiidiotype network; showing evidence of IgG subclasses deficiency (mostly IgG1 and IgG3) may help identify patients who can benefit from iv. immunoglobulin treatment.

[Sinonasal polyposis associated with a deficiency subclass immunoglobulin G: Place of substitution immunoglobulins]. / Polypose nasosinusienne associée à un déficit en sous-classes d'Immunoglobuline G: place de la substitution en immunoglobulines polyvalentes.

PURPOSE: To study the effect of the introduction of a substitution by intravenous Immunoglobulins (Ig IV) at patients with immunoglobulins G (IgG) subclasses deficiency and nasal polyposis. MATERIAL AND METHODS: Prospective study concerning five patients with IgG subclasses deficiency and nasal polyposis treated by Ig IV. Rhinologic, otologic and pulmonary symptoms, exacerbations of nasal polyposis, chronic otitis and asthma as well as the number of antibiotics and corticoids treatments were counted during the Ig IV substitution. OBJECTIVES: To study the association between IgIV substitution and the number of exacerbations of nasal polyposis, chronic otitis, asthma and the number of antibiotics and corticoids treatments in patients with IgG subclasses deficiency and nasal polyposis. RESULTS: Five patients with a IgG subclass deficiency and nasal polyposis were substituted. The number of antibiotics and corticoids cures increased at one patient and remained stable at four others. The number of sinus, ear and lung infections as well as the global rhinologic score of symptoms and the endoscopic stage of the nasal polyposis remained stable. In the absence of efficiency of the treatment, this one was interrupted at the end of 6 months for patients n° 1 and n° 3, 24 months for patient n° 4 and 42 months for patient n° 5. CONCLUSION: The current study failed to highlight clinical improvement in patients wih IgG subclasses deficiency and nasal polyposis treated by Ig IV. A previous study had not allowed to find a link between IgG subclasses deficiency and severity of nasal polyposis, what seems to be confirmed by the absence of improvement brought during the substitution of this deficit in the current study.

[Assessment of immunoglobulins in a long-term non-interventional study (SIGNS Study). Rationale, design, and methods]. / Prospektive Versorgungsforschungsstudie zur Therapie mit Immunglobulinen (SIGNS): Rationale, Design und Methodik.

Non-modified human immunoglobulins (IgG) are standard of care for replacement therapy with primary (inherited) immunodeficiencies, and secondary immunodeficiencies due to multiple myeloma (MM) or chronic lymphocytic leukemia (CLL). Further, they have effectively been used as immunomodulation in neurological autoimmune diseases such as Guillain-Barré syndrome (GBS), chronic inflammatory demyelinating polyneuropathy (CIDP), and multifocal motor neuropathy (MMN). A variety of IgG preparations for intravenous and subcutaneous use are available. In view of the broad range of indications, data on the utilization of the IgG preparations in everyday clinical care are of high clinical interest. Furthermore, data on the outcomes of IgG therapy outside the setting of controlled clinical trials are needed. Therefore, the SIGNS study (Assessment of Immunoglobulins in a Long-Term Non-Interventional Study) was set up as a non-interventional prospective open-label cohort study and was approved by the ethics committee. Led by an interdisciplinary steering board, hospital- and office-based investigators in 30-40 centers throughout Germany (neurologists, pediatricians, oncologists, other) will document approximately 300 patients, and will follow them for at least 2 years. Patients of both genders and any age are eligible if they have received, or are scheduled for, IgG therapy for primary or severe secondary immunodeficiency or neurological autoimmune diseases, and have provided written informed consent. No exclusion criteria have been defined in order to minimize selection bias. Long-term outcome data will be collected on patient characteristics in the various indications, drug utilization (e.g., treatment and dosing patterns), effectiveness (i.e., number of infections), tolerability, health-related quality of life, and economic variables (number of hospitalizations, sick-leave days, etc.) with the possibility to estimate direct costs. For the neurological autoimmune diseases, detailed data will be gathered, among others, on neurological function, muscular function, physical function (grip strength, INCAT disability scale, etc.) and stabilization or progression of symptoms over time. Data collection in SIGNS is performed using a secure internet site and an MySQL database. A number of quality measures are routinely performed including automated plausibility checks at data entry, queries, and on-site monitoring with source data verification. It is expected that SIGNS will contribute to optimization of therapy in this diverse patient population.

Transient hypogammaglobulinemia of infancy: intravenous immunoglobulin as first line therapy.

IVIG (Intravenous immunoglobulin) have significantly improved the prognosis and the quality of life of immunodeficient patients and are routinely used as substitutive therapy. Transient hypogammaglobulinemia of infancy (THI) is a primary humoral immunodeficiency characterized by a transient IgG defect, but is not considered as a disease that justifies substitutive treatment and thus the use of IVIG as an alternative to antibiotic prophylaxis remains controversial also in symptomatic children. We treated 13 THI children severely symptomatic with IVIG (400mg/kg/every 3 weeks ) for a limited period (2 or 3 months) and followed them for 1 to 3 years. During the follow-up, the frequency of overall infections decreased approximately tenfold (from 0.39 to 0.047 infection/month per child) and no severe infections were reported. Although this study lacks untreated controls, the results suggest that the observed clinical improvement is correlated to IVIG therapy. Furthermore, our study suggests that the infused IVIG have no long-term effect on endogenous IgG production and do not lengthen the immunodeficiency condition since all children produced a normal amount of specific IgG in response to vaccination carried out 5 months after the end of infusions. In conclusion, our results suggest that IVIG may stop the vicious circle of infection-immunodeficiency and should be considered as a first line therapy in highly symptomatic THI children.

Immunological and clinical profile of adult patients with selective immunoglobulin subclass deficiency: response to intravenous immunoglobulin therapy.

Selective immunoglobulin (Ig)G3 subclass deficiency in adults, especially its immunological profile, has not been described previously in detail. Therefore, a retrospective chart review was conducted to characterize the immune profile and clinical manifestations in adult patients with selective IgG3 deficiency. We reviewed the charts of 17 adult patients attending our subspeciality immunology clinic with a diagnosis of selective IgG3 deficiency. The following immunological test results were recorded: lymphocyte subsets, proliferative response to mitogens (phytohaemagglutinin, concanavalin A, pokeweed mitogen) and soluble antigens (mumps, Candida albicans, tetanus toxoid), specific antibody response to tetanus toxoid and pneumococcal antigens, neutrophil oxidative burst and natural killer cell cytotoxicity. In addition, we recorded information about the types of infections and other associated diseases, and response to intravenous immunoglobulin therapy (IVIG). In the majority of patients, lymphocyte subsets were normal. Proliferative responses to mitogens and antigens were decreased in 33% and 40% of patients, respectively. Specific antibody responses to tetanus were normal; however, responses to various pneumococcal serotypes were impaired in a subset of patients. Patients suffered from recurrent upper respiratory tract infections, which usually decreased in frequency and severity following treatment with IVIG. The majority of these patients also had concurrent atopic diseases in the form of allergic rhinitis or asthma. Selective IgG3 subclass deficiency should be considered in adults with recurrent upper respiratory tract infections with or without allergic rhinitis or asthma, who may have normal levels of total IgG. IVIG appears to be an effective therapy.

Efficacy of intravenous gammaglobulin for immunoglobulin G subclass and/or antibody deficiency in adults.

BACKGROUND: The clinical significance and efficacy of treating patients who have immunoglobulin (Ig) G subclass deficiency and/or antibody deficiency with Ig-replacement therapy has been debated. There are no clear guidelines to recommend intravenous gammaglobulin (IgIV) in these patients as there are few published studies documenting its efficacy. METHODS: We studied in an open-label protocol 10 adult patients with recurrent respiratory infections and IgG subclass and/or antibody deficiency. All patients received monthly IgIV for 12 months and then were observed for 3 months without IgIV infusions. We studied quality of life, incidence of infections, need for antibiotics, frequency of hospitalizations due to infections, IgG subclass and antibody (tetanus and pneumococcal) levels. Innate immunity was evaluated by studying the status of Toll-like receptors and polymorphisms, mannan-binding lectin levels and genotypes. Correction of the immune defects during IgIV therapy was evaluated. RESULTS: Monthly IgIV significantly improved quality of life, decreased the number of infections and the need for antibiotics, and improved IgG subclass and antibody serum levels. No consistent finding of innate immunity could be detected. CONCLUSIONS: IgIV could be beneficial in patients with IgG subclass or antibody deficiency.

Subcorneal pustulosis with combined lack of IgG/IgM and monoclonal gammopathy type IgA/Kappa.

Subcorneal pustulosis (Sneddon-Wilkinson disease) is a rare inflammatory neutrophilic dermatosis. While subcorneal pustulosis is often associated with an IgA gammopathy, the combined lack of IgG/IgM seen in our case is rare. An 83-year-old man with combined lack of IgG/IgM and monoclonal gammopathy type IgA/Kappa presented with subcorneal pustules. Intravenous immunoglobulin therapy led to complete regression and might be another therapeutic option.

Collagenous duodeno-ileo-colitis with transient IgG deficiency preceded by Yersinia enterocolitica intestinal infection: case report and review of literature.

A case-report of a man with chronic diarrhoea is presented. After an unsuccessful treatment of an intestinal yersioniosis, the diagnosis of collagenous intestinal disease affecting duodenum, ileum and colon was made. In addition, a IgG transient deficiency was observed. The literature about gastrointestinal involvement, concomintant infection by Yersinia and IgG deficiency in collagenous colitis is reviewed.

Immunoglobulin prophylaxis in 350 adults with IgG subclass deficiency and recurrent respiratory tract infections: a long-term follow-up.

350 adult patients in Sweden were included in a retrospective study covering more than 2000 patient-y, to evaluate the efficacy of immunoglobulin (Ig) prophylaxis. All patients had selective or combined IgG subclass deficiency, without IgA deficiency, and suffered from recurrent respiratory tract infections (RTIs). The patients had been given Ig prophylaxis for 0.5-21 y (mean 5.5 y). In total, 164/350 of the patients had a concomitant lung disease. Because of the heterogeneity of this retrospective material we evaluated only those patients with 4 or more antibiotic-demanding (i.e. presumably bacterial) episodes of RTI per y treated with an Ig dose of about 100 mg/kg/week (132/350). The frequency of antibiotic treated RTIs prior to and during latest y/s of Ig prophylaxis was compared. No difference in response could be found between patients with and without chronic lung diseases. In 92/132 a > or = 50% reduction of the rate of episodes of antibiotic-demanding RTIs was recorded (p < 0.001). The overall reduction of the RTI frequency was for IgG1 57%, IgG2 59%, IgG3 63% and for the combinations 61% (all p<0.001).

Isolated IgG3 deficiency in children: to treat or not to treat? Case presentation and review of the literature.

Immunoglobulin G3 (IgG3) subclass deficiency has received rather little attention thus far. In this report, the clinical and immunologic characteristics of six children with isolated IgG3 deficiency are discussed. The currently available literature on IgG3 deficiency is reviewed with specific emphasis on the peculiarities of the IgG3 subclass, the clinical relevance of IgG3 deficiency as well as the therapeutic options.

Women with primary antibody deficiencies requiring IgG replacement therapy: their perception of prenatal care during pregnancy.

OBJECTIVE: To investigate how a group of women with primary antibody deficiencies (PAD) and receiving replacement therapy with IgG experienced the care they received in their prenatal clinics in relation to PAD and IgG therapy. DESIGN: An exploratory study using a written questionnaire. SETTING: The study originates from an immunodeficiency unit but evaluates care experienced at prenatal clinics. PARTICIPANTS: Nine women (25-43 years) attending an immunodeficiency unit and who fulfilled inclusion criteria for simultaneously having PAD, replacement IgG therapy, and full-term pregnancy (the latter within the past 5 years). MAIN OUTCOME: Women's perception of the response of midwives and physicians at their prenatal clinics to their PAD and IgG therapy during pregnancy. RESULTS: Women perceived that the obstetricians and the midwives had insufficient knowledge about PAD and IgG replacement therapy. Two women reported that their IgG therapy during pregnancy had been questioned. All nine women felt marginalized and unheard by staff regarding their PAD and need for IgG therapy. However, the women were satisfied with the checkups regarding the pregnancy as such. CONCLUSIONS: This study is the first attempt to investigate the prenatal experience of women with PAD (Search of PubMed, 1980 to present, including search terms primary immunodeficiency, pregnancy, and prenatal care). This study demonstrates that increased knowledge about PAD and IgG replacement therapy among midwives and physicians working in prenatal care clinics is needed. This can prevent misleading advice that puts the health of the mother and her fetus at risk. Sensitizing staff about this special group of women can create conditions in which women feel respected, heard, and satisfied with their prenatal care.

Giardia lamblia infection in a patient with myotonic dystrophy.

Myotonic dystrophy is an autosomal dominant muscle disorder characterized by muscle wasting and weakness and a number of other systemic abnormalities. Some patients have hypo-IgG that is asymptomatic in most of them. We report the case of a 42-year-old woman with myotonic dystrophy and hypo-IgG who experienced asthenia and weight loss secondary to Giardia lamblia bowel infection.