Pregnancy does not increase the likelihood of illness.
The incidence of pneumonia is 1.5: 1000 or 1: 660 pregnant. Pregnant women with this disease usually have a concomitant pathology, such as anemia, HIV infection, and drug dependence. Pneumonia account for 4-5% of all cases of hospitalization of pregnant women due to extragenital pathology and are the most common cause of maternal mortality from extragenital infections.
The main symptoms are: dyspnea (65%), cough (90%), sputum production (65%), chest pain (50%), fever, tachycardia, wheezing during auscultation, x-ray infiltrates.
When diagnosing pneumonia, it is necessary to exclude diseases that are similar in clinical signs:
pulmonary embolism;
chemical aspiration pneumonitis;
amniotic fluid embolism;
pulmonary edema, with sepsis, tocolysis, preeclampsia.
The spectrum of microorganisms that cause pneumonia during pregnancy does not differ from that outside pregnancy.
Half of pneumonia has a bacterial etiology.
In a quarter of cases, the pathogen is not detected.
When the causative agent is identified, it turns out to be: S. pneumoniae – 50%, influenza A virus – 19%, Chlamydia pneumoniae – 13%, H. influenzae – 7%, Mycoplasma pneumoniae – 3%, Legionella pneumophila – 3%.
Due to the weakening of the cellular component of immunity during pregnancy, the risk of severe pneumonia and dissemination of the disease increases if it is caused by an atypical pathological agent – herpes simplex virus, influenza, chickenpox and coccidioidomycosis. The most common microorganisms that cause pneumonia are shown in Table 4.
The risk to the mother and the fetus
The risk of miscarriage and premature pregnancy increases if the disease occurs with a high temperature: more than 39 °, is accompanied by acidosis, bacteremia and requires mechanical ventilation.
Most cases of pneumonia are caused by microorganisms that do not have a pathological effect on the fetus, with the exception of viruses, especially varicella pneumonia.
All pregnant women with pneumonia must be screened for HIV infection, which threatens the fetus.
Caesarean section does not improve the patient’s respiratory function and is performed only according to obstetric indications.
Vaccination against influenza is recommended for all women, regardless of gestational age, if it falls on the season of the expected epidemic. The vaccination rate is 99%. The incidence is reduced by 15 times.
Pneumococcal vaccination (70% effectiveness) is recommended on the eve or during pregnancy for women with conditions such as diabetes mellitus, bronchial asthma, chronic heart and lung diseases, and diseases of the immune system. Prophylaxis is mandatory for women with a removed spleen, with functional hyposplenism (sickle cell anemia), as well as for women living in social shelters and in places of detention.
Prevention of pneumocystis pneumonia is carried out by trimethoprim-sulfamethoxazole and is necessary for HIV infection complicated by oropharyngeal candidiasis or a reduced level of CD4 cells: less than 200 / μl.

Recommendations for the prevention of chickenpox pneumonia:
The incidence of chickenpox in pregnant women is low: 7:10,000.
The presence of antibodies (immunity) is observed in more than 90% of pregnant women.
Non-immunized women of childbearing age are recommended to be vaccinated against chickenpox virus (Varivax live vaccine) with an efficiency of 87%.
Pregnant women and women planning a pregnancy are not vaccinated.
When a pregnant woman comes in contact with chickenpox, it is necessary to determine the presence of antibodies to the virus (ELISA). In their absence, the introduction of specific immunoglobulin within 96 hours of contact is necessary: ​​125 IU / 10 kg of body weight (up to 625 IU) intramuscularly.
Due to the high probability of developing pneumonia in pregnant women with chickenpox: 10% (9-22%), for all women with respiratory symptoms not immunized against varicella, no later than 10 days from the moment of their appearance, intravenous administration of acyclovir is recommended: 10-15 mg / kg 3 times a day for 7 days.
The greatest risk of a newborn’s disease exists when the mother is infected within 5 days before or after childbirth: infection – 10-20%, mortality – 20-30%. If childbirth cannot be delayed for 5-7 days, the newborn is immediately administered with immunoglobulin: 125 units intramuscularly.
Diagnostics The
“Gold Standard” in diagnosing pneumonia is changes in the chest radiograph. Any pregnant woman with suspected pneumonia should undergo an X-ray examination of the lungs: the
radiation load on the fetus is minimal (equivalent to a one-day radiation background);
the risk to the fetus from undiagnosed pneumonia is higher than the risk from the study;
radiologists unreliably differentiate bacterial pneumonia from non-bacterial.
Not mandatory: Gram-stained sputum smears, culture of sputum (in half the cases it is not possible to isolate the etiological agent), serological tests, cold agglutination, bacterial antigens.
When conducting a differential diagnosis, you can use radioscopic ventilation-perfusion scanning or computed tomography: for pregnant women with high fever, purulent sputum, chest pain and x-ray data, the diagnosis of infectious pneumonia is not in doubt, and in the case of fever, in the absence of sputum and conflicting clinical and radiological findings should rather think about pulmonary infarction than the infectious genesis of pneumonia.
The most important decision in the management of pregnant women with pneumonia is the decision about hospitalization.
All pregnant women with suspected pneumonia should be hospitalized.
Antibacterial treatment is empirical.
Recommended antibiotic treatment for pregnant women with pneumonia recommended by the United States Society for Infectious Diseases (IDSA), the British Thoracic Society (BTS), and the American Thoracic Society (ATS)

A. Uncomplicated pneumonia (pathogens – pneumococcus, mycoplasma, chlamydia).

Standard: erythromycin 250 mg 4 times a day per os 10-14 days.

Alternative: azithromycin 500 mg per os once daily for the first day and 250 mg per os daily for the next 4 days.

B. Pneumonia in patients requiring intensive treatment (the presence of complications or with suspected staphylococcus aureus and Haemophilus pneumonia as causative agents of pneumonia).

Ceftriaxone 2 g iv once with erythromycin 500 mg every 6 hours (azithromycin 500 mg daily in case of poor tolerance of erythromycin). After normalizing the temperature and stabilizing the state, erythromycin 250-500 mg per os 4 times a day + cefuroxime acetyl 500 mg per os 2 times a day. The total duration of antibiotic therapy is 14 days.

In addition:
If the patient receives azithromycin instead of erythromycin, then the duration of treatment should not exceed 5 days, since this antibiotic has a long half-life. Treatment with azithromycin is carried out according to the scheme: 500 mg on the first day and 250 mg daily from 2 to 5 days.
Up to 20% of pneumococci are resistant to penicillin and erythromycin. Of these, only 0.5% are resistant to fluoroquinolones.
In exceptional cases, monotherapy with fluoroquinolones acting on pneumococcus is possible (ciprofloxacin, ofloxacin, levofloxacin).
At elevated temperatures, acetaminophen (paracetamol) is considered the drug of choice.
Respiratory failure due to pneumonia is one of the reasons a pregnant woman is admitted to the intensive care unit. Such a patient requires additional oxygen supply and monitoring of the gas composition of arterial blood.
The partial tension of oxygen in the blood should be maintained at a level sufficient for adequate oxygenation of the fetus: at least 70 mm Hg. The recommended patient position is on the left side.
Clinical improvement occurs after 48-72 hours, the fever disappears after 2-4 days. The deterioration of the condition with the continuation of the fever is a poor prognostic sign requiring dynamic x-ray examination (table 5).
Even with clinical improvement, an increase in the size of infiltrates in the lungs is possible.
Approximately 20% of patients develop pleural effusion.
Intubation of the trachea and mechanical ventilation is required in 7% of patients (12-15% of all pregnant women requiring mechanical ventilation).
Flu pneumonia:
Develops in 10% of pregnant women with the flu. Pregnancy increases the risk of viral pneumonia, which is especially high if flu symptoms persist for more than 5 days.
Primary viral pneumonia is the most severe and can cause maternal mortality. Scanty sputum and interstitial infiltrates on the radiograph are characteristic.
Secondary pneumonia, which is more common, is a consequence of bacterial superinfection with streptococci and staphylococci, manifesting itself 2-3 days after the patient’s condition improves.

Amantadine and rimantadine at a dose of 200 mg per day are effective for the prevention and treatment of influenza, preventing 50% to 90% of the clinical manifestations of the infection. Treatment initiated within 48 hours of the onset of the disease reduces its severity. Remember that these drugs in high doses are teratogens in animals. For humans, their teratogenicity has not been proven.
Neuraminidase inhibitors: oseltamivir 75 mg twice daily orally and zanamivir 10 mg twice daily in inhalations are effective in treating influenza. When used for prophylaxis, the clinical manifestations of the disease are prevented in 80-85% of cases. Animal teratogens are not. Teratogenicity for humans has not been studied.
Acute Respiratory Syndrome

Acute respiratory syndrome (SARS) is a life-threatening disease caused by coronavirus. First described in China in 2002. Mortality is approximately 5%.
Transmission is carried out with droplets of saliva, in close contact with infected body secrets and debris. The clinical picture is almost indistinguishable from ordinary pneumonia. Three phases of the disease are described:
in the first week there is virus replication and cytolysis, accompanied by fever and muscle pain;
during the second week, the patient has intermittent fever, diarrhea and hypoxemia. Antibodies to the virus appear (seroconversion) and the viral load decreases: the
third phase of the disease is noted in 20% of patients: acute respiratory distress syndrome develops, requiring mechanical ventilation.
The x-ray picture is not specific. Possible lymphopenia, thrombocytopenia, increased activity of lactate dehydrogenase.
Outcomes in pregnant women are worse than in non-pregnant women.
There were no cases of transmission of the disease to the newborn.

Treatment: The
optimal treatment has not been developed. It is carried out by broad-spectrum antibiotics.
Pregnancy experience:
clarithromycin 500 mg twice a day, amoxiclav 375 mg three times a day;
ribavirin and corticosteroids are prescribed to suppress virus replication and optimize the immune response, and only in severe cases of the disease.

The safety of drugs during pregnancy.
Erythromycin is not a teratogen for humans, but the use of erythromycin ester estolate during pregnancy is often accompanied by a subclinical reversible hepatotoxic effect, which is not observed in other forms of erythromycin – ethyl succinate and stearate.
The safety of azithromycin during pregnancy is shown in a few studies. Due to the fact that azithromycin is an expensive drug, it should be used in cases where erythromycin is poorly tolerated by the patient.
Clarithromycin and levofloxacin are recommended for the treatment of cases of resistant pneumococcal pneumonia in non-pregnant women, but despite this, these drugs should not be used during pregnancy. Clarithromycin demonstrated a teratogenic effect in an animal experiment and can be used in pregnant women only as a “despair therapy”.
Although fluoroquinolones do not have a fetotoxic or teratogenic effect in animals, their use during pregnancy and in pediatric practice is not recommended due to the fact that ciprofloxacin and ofloxacin can cause irreversible arthropathy in an experiment. Modern authors consider this danger to be greatly exaggerated, but so far these drugs are still considered contraindicated during pregnancy.
Tetracyclines should not be used during pregnancy, since they adversely affect the skeletal system and the formation of teeth in the fetus.

It is important to remember: in connection with an increase in renal clearance during pregnancy, the dosage of antibiotics should be increased.